Systems and methods for modular power amplifiers

ABSTRACT

Systems and apparatuses are disclosed that include an RF generator configured to generate RF signals having a wavelength. Amplifiers are configured to receive and amplify the RF signals from the RF generator and are separated from each other by a separation distance in a range between about 0.2 times the wavelength and about 10.0 times the wavelength. A power management system is configured to control one or more of the amplifiers based on information received that is associated with the RF signals.

RELATED APPLICATION(S)

This application is a continuation in part of U.S. application Ser. No.16/908,476 filed Jun. 22, 2020 titled SYSTEMS AND METHODS FOR MODULARPOWER AMPLIFIERS, which is related to both U.S. application Ser. No.16/779,036 filed Jan. 31, 2020 titled “APPARATUS AND METHOD FORSYNCHRONIZING POWER CIRCUITS WITH COHERENT RF SIGNALS TO FORM A STEEREDCOMPOSITE RF SIGNAL” and U.S. Provisional Application No. 62/817,096,filed Mar. 12, 2019, the contents of each are hereby incorporated byreference.

DESCRIPTION OF THE RELATED ART

Radio-frequency (RF) applications often involve amplifying a RF signalto a power level suitable for applications in defense, policing,industrial applications, or the like. Amplifier arrays can be arrangedin a 2D configuration, such as arranged on a single circuit board or thelike, and some such circuits can be of significant size in order tocontain the required number of amplifiers. Other approaches for RFamplification include radial combiners or Gysel combiners. While theyallow some degree of redundancy such that the combiner can function ifone is damaged, such combiners are often connectorized, making themdifficult to repair.

SUMMARY

A modular power amplifier is disclosed that includes a power amplifiersubsystem having a first 90 degree hybrid block configured to receive anRF signal and output a split RF signal with components having a 90degree phase shift, a second 90 degree hybrid block configured toreceive and combine the split RF signal by removing the 90 degree phaseshift; and a high-power amplifier configured to amplify at least one ofthe components of the split RF signal. The modular power amplifier alsoincludes a power distribution module configured to regulate an amount ofpower input to the high-power amplifier and a power sequencer configuredto control the timing of power delivery by the power distributionmodule.

In some variations, the first 90 degree hybrid block can includecomprising a resistor configured to dissipate at least a portion of RFpower going through the first 90 degree hybrid block when the RF poweris above a threshold. Also, the modular power amplifier can include anumber of power amplifier subsystems, each of the power amplifiersubsystems including the first hybrid block and the second hybrid block,where at least one of the plurality of the power amplifier subsystemsreplaces a high-power amplifier in another of the power amplifiersubsystems to form a scaled power amplifier assembly.

Other variations can include waveform generation circuitry having afield-programmable gate array and a digital-to-analog converter,together configured to receive digital commands and a clocksynchronization signal and to output the RF signal to the poweramplifier subsystem and a phase lock loop circuit configured to provideclocking to the power amplifier synchronized with the clocksynchronization signal.

In an interrelated aspect, also disclosed is a system having a poweramplifier subsystem with a splitter configured to split an RF signalinto a first RF component and a second RF component, a first high-poweramplifier configured to amplify and output the first RF component, and asecond high-power amplifier configured to amplify and output the secondRF component. There may also be a differential antenna having a firstinput operatively connected to the first high-power amplifier to receivethe first RF component and a second input operatively connected to thesecond high-power amplifier to receive the second RF component.

In another interrelated aspect, a modular power amplifier can have twopower amplifier subsystems, each comprising: a first 90 degree hybridblock configured to receive an RF signal and output a split RF signalwith components having a 90 degree phase shift, a high-power amplifierconfigured to amplify at least one of the components of the split RFsignal, and a second 90 degree hybrid block configured to receive,combine, and output the split RF signal by removing the 90 degree phaseshift. There may also be a differential antenna configured to receivethe output of the second 90 degree hybrid blocks of the two poweramplifier subsystems.

In yet another interrelated aspect, a three-dimensional power amplifiercan include a first high-power amplifier configured to receive a firstRF signal and output a first amplified RF signal, a second high-poweramplifier configured to receive a second RF signal and output a secondamplified RF signal, the second high-power amplifier having a differentorientation than the first high-power amplifier, the differentorientations causing a reduction in electromagnetic interference betweenthe first high-power amplifier and the second high-power amplifier.

In some variations, the first high-power amplifier and the secondhigh-power amplifier are of generally planar construction and thegenerally planar amplifiers have the different orientations.

In other variations, the different orientations have an angle of 90degrees between them to form a portion of a square distribution ofhigh-power amplifiers.

In some variations, the three-dimensional power amplifier can include acooling component located between the first high-power amplifier and thesecond high-power amplifier. Furthermore, the first high-power amplifierand the second high-power amplifier can be configured to receive thefirst RF signal and the second RF signal, both signals having awavelength, and the first high-power amplifier and the second high-poweramplifier are separated by at least approximately half of thewavelength.

In an interrelated aspect, a system can include an RF generatorconfigured to generate RF signals having a wavelength, amplifiersconfigured to receive and amplify the RF signals from the RF generatorand that are separated from each other by at least approximately half ofthe wavelength, and a power management system configured to control oneor more of the amplifiers based on information received that isassociated with the RF signals.

In some variations, the separation between the plurality of amplifierscan be between approximately 0.2 times the wavelength and approximately10 times the wavelength. For example, the separation between theplurality of amplifiers can be approximately 0.25 times the wavelength,0.3 times the wavelength, 0.4 times the wavelength, 0.5 times thewavelength, 0.6 times the wavelength, 0.7 times the wavelength, 1.0times the wavelength, 1.5 times the wavelength, 2.0 times thewavelength, 2.5 times the wavelength, 3.0 times the wavelength, 4.0times the wavelength, 5.0 times the wavelength, 7.0 times thewavelength, 10.0 times the wavelength, or any separation therebetween.The wavelength can be in a range between about 500 MHz and about 20.0GHz, such as, for example, within the L-band, the S-band, the K-band,etc. In various implementations, the separation between the amplifierscan be in a range between approximately 2-18 inches or 3-7 inches. Inother variations, the RF generator can be configured to generate anumber of wavelengths of RF signals and the separation between theamplifiers is approximately the smallest wavelength of the wavelengths.

In other variations, the power management system can be configured toautomatically determine voltages and/or currents required to turn-onand/or turn-off corresponding amplifiers in the amplifiers.

In an interrelated aspect, a system includes an RF generator can beconfigured to generate RF signals having a wavelength, amplifiersconfigured to receive and amplify the RF signals from the RF generatorand that are separated from each other by at least approximately half ofthe wavelength, a sensor configured to detect at least one sensedcharacteristic associated with at least one amplifier of the amplifiers,and a power management system configured to control one or more of theamplifiers based on the sensed characteristic.

In yet another interrelated aspect, a computer program product isdisclosed that causes operations including transmitting, from a modularcomponent, a request for an IP address, transmitting, from the modularcomponent, a subnet address of the modular component based on a portthat the modular component is connected to, and assigning, by an addressserver, an IP address to the modular component based on the subnetaddress of the modular component.

In some variations, the modular component can be a modular poweramplifier configured to amplify an RF signal. The operations can includeproviding a bias voltage to the modular power amplifier based on the IPaddress. Also, the address server can be a Radio FrequencySystem-on-Chip (RFSoC).

Implementations of the current subject matter can include, but are notlimited to, methods consistent with the descriptions provided herein aswell as articles that comprise a tangibly embodied machine-readablemedium operable to cause one or more machines (e.g., computers, etc.) toresult in operations implementing one or more of the described features.Similarly, computer systems are also contemplated that may include oneor more processors and one or more memories coupled to the one or moreprocessors. A memory, which can include a computer-readable storagemedium, may include, encode, store, or the like, one or more programsthat cause one or more processors to perform one or more of theoperations described herein. Computer implemented methods consistentwith one or more implementations of the current subject matter can beimplemented by one or more data processors residing in a singlecomputing system or across multiple computing systems. Such multiplecomputing systems can be connected and can exchange data and/or commandsor other instructions or the like via one or more connections, includingbut not limited to a connection over a network (e.g., the internet, awireless wide area network, a local area network, a wide area network, awired network, or the like), via a direct connection between one or moreof the multiple computing systems, etc.

The details of one or more variations of the subject matter describedherein are set forth in the accompanying drawings and the descriptionbelow. Other features and advantages of the subject matter describedherein will be apparent from the description and drawings, and from theclaims. While certain features of the currently disclosed subject matterare described for illustrative purposes in relation to particularimplementations, it should be readily understood that such features arenot intended to be limiting. The claims that follow this disclosure areintended to define the scope of the protected subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, show certain aspects of the subject matterdisclosed herein and, together with the description, help explain someof the principles associated with the disclosed implementations. In thedrawings:

FIG. 1 is a simplified block diagram illustrating an amplifier andcontrol system, in accordance with certain aspects of the presentdisclosure;

FIG. 2 is a simplified block diagram illustrating a modular poweramplifier, in accordance with certain aspects of the present disclosure;

FIG. 3a is a simplified block diagram illustrating an amplifiersubsystem, in accordance with certain aspects of the present disclosure;

FIG. 3b is a simplified block diagram illustrating an amplifiersubsystem implemented with a differential antenna, in accordance withcertain aspects of the present disclosure;

FIG. 3c is a simplified block diagram illustrating an amplifiersubsystem implemented with an antenna array, in accordance with certainaspects of the present disclosure;

FIG. 3d is a simplified block diagram illustrating multiple amplifiersubsystems implemented with a differential antenna, in accordance withcertain aspects of the present disclosure;

FIG. 4 is a simplified diagram illustrating the combining of amplifiersubsystems into a scaled power amplifier assembly, in accordance withcertain aspects of the present disclosure;

FIG. 5 is a simplified block diagram illustrating the generation of RFsignals for amplification, in accordance with certain aspects of thepresent disclosure;

FIG. 6 is a simplified block diagram illustrating a parallel amplifiersystem, in accordance with certain aspects of the present disclosure;

FIG. 7 is a simplified block diagram illustrating a 3D power amplifier,in accordance with certain aspects of the present disclosure;

FIG. 8 is a simplified diagram illustrating modular power amplifier, inaccordance with certain aspects of the present disclosure;

FIG. 9 is a simplified diagram illustrating a rack for multiple modularpower amplifiers, in accordance with certain aspects of the presentdisclosure;

FIG. 10 illustrates an implementation similar to the system of FIG. 1,but with additional details provided for a number of components, inaccordance with certain aspects of the present disclosure;

FIG. 11 illustrates an implementation of a power management system, inaccordance with certain aspects of the present disclosure;

FIG. 12 is a schematic illustration including an amplifier that is partof an amplifier chain controlled by a power management system, inaccordance with certain aspects of the present disclosure;

FIG. 13 illustrates an exemplary correlation between the drain currentand the device temperature for an implementation of a FET amplifier, inaccordance with certain aspects of the present disclosure;

FIG. 14 illustrates an exemplary reduction in temperature due to anadjustment in gate bias voltage, in accordance with certain aspects ofthe present disclosure;

FIG. 15 illustrates an example of currents required to charge storagecapacitors for amplifiers utilizing drain switching, in accordance withcertain aspects of the present disclosure;

FIG. 16 illustrates an example of currents required to charge storagecapacitors for amplifiers utilizing gate switching, in accordance withcertain aspects of the present disclosure;

FIG. 17 illustrates a flow chart of exemplary operations for currentsensing performed by the power management system, in accordance withcertain aspects of the present disclosure;

FIG. 18 illustrates an exemplary process for monitoring and tuning anamplifier, in accordance with certain aspects of the present disclosure;

FIG. 19 illustrates an exemplary display showing the health of anamplifier system, in accordance with certain aspects of the presentdisclosure; and

FIG. 20 illustrates an exemplary block diagram depicting a computerarchitecture for providing distributed IP addresses to amplifiermodules, in accordance with certain aspects of the present disclosure.

DETAILED DESCRIPTION

The present disclosure provides examples of systems and methods forpower amplifiers that provide several benefits over the state of theart. For example, amplifier systems are disclosed that have higher powerdensity, are compact, scalable, have improved cooling, have reducedelectromagnetic interference (EMI), etc. Such features are important forproviding compact, high-power RF amplification, with applications inindustry, defense, radar, communications, signal jammers, etc.

The overall system, as shown in FIG. 1, is designed for high power radiofrequency transmissions, such as in high power microwave, directedenergy, radar, and communications applications. The mission computer 120runs the software code controlling the system, generally receivescontrol commands, and prioritizes the hardware according to thosecommands. For example, the mission computer, in a directed energyapplication, receives inputs about the location of targets such asautomated target cues from an external radar, from a user who is using auser console to select targets, or from an automated target recognitionand classification software based on image or radar inputs. The missioncomputer 120, also receives firing commands from a user such as whetherto fire. The mission computer has many different modes it can run evenfor a firing command such as to raster a beam around a target, how manyshots to fire, and in target swarm scenarios, which target to prioritizefirst for firing. Resource management decisions such as which targets tofire on first, such as the closest target, how many targets can be firedon with a single beam such that multiple targets fit within the samebeam width, how fast the pulse width of the waveform needs to be, whatfrequency and what pulse repetition interval the waveform needs to beare all automatically decided based on a target recognition system orthrough user command resides in the mission computer 120. The missioncomputer, 120 can translate these into beam steering commands andwaveform commands into phase and waveform commands for the hardware toproduce to send to the waveform generator or the RF field programmablegate array (FPGA) 150. These waveform commands are also synchronizedwith the turning on and turning off of line replaceable amplifiermodules, 170. In some embodiments the waveform is generated directly inthe amplifier modules 170, if a direct digital synthesizer or waveformgenerator is contained in the amplifier modules, 170, instead of thewaveform generator RF FPGA 150. The amplifier modules 170 can beoptionally integrated with a temperature cooling system 180 which canprevent overheating of the amplifier modules 170. The unit is generallyconnected to a generator or some other power Alternating Current (AC)power source, and this connection is made through the AC power system130. The AC power system often has current monitoring, current control,and on/off switches that are controlled in the preferred embodiment bythe mission computer 120. The AC power system also translates voltagesand can also translate from AC to DC with AC/DC conversion. In somesystems this AC/DC conversion happens in a centralized way right afterthe AC power is received from the AC power unit130, or in otherembodiments the AC/DC conversion is done locally on each modular poweramplifier 170, where each one has its own power distribution unit 140.In some embodiments the AC/AC conversion and AC/DC conversion is done inmultiple steps, where voltage and current levels are changed, this isdone in the AC power unit 130. The power distribution unit (PDU), 140can generally translate the voltage to the final direct current (DC)voltage needed by each amplifier input. In the preferred embodiment,there are 65 volt, 50 volt, and 12 volt regulators on board the powerdistribution unit for the modular power amplifier voltages that areneeded. The PDU 140 regulates these voltages, also stores energy toprovide impulses of power without the voltage level drooping, andgenerally is in charge of providing a DC voltage required to drive poweramplifiers in amplifier modules 170. The PDU 140 may also have currentsensors, current monitoring, and current limiters. The system can beconfigured as a phased array configuration, so multiple power amplifiercan be connected to an array of radiating antennas 190. These antennaelements 190, can have special connectors designed to handle very highvoltage levels and power levels, in the directed energy application. Theantenna elements can comprise matching circuits that match theirimpedance to the impedance of the modular power amplifiers. In otherembodiments of this system, the antenna elements, 190 are also used toreceive RF energy and this RF energy is fed back into thetransmit/receive modules, 170. Overall, the mission computer 120commands waveforms and the power sources, the power sources 130 and 140translate power into the precise voltages and currents needed on thepower amplifiers in the amplifier modules 170 that amplify the RF signalto very high levels and radiate out of the antennas 190.

One exemplary embodiment utilizing concepts disclosed herein isillustrated in FIG. 1. Shown is a user input device 110, which can be acomputer, tablet, smartphone, or any computing device capable ofreceiving text, mouse, touch, voice commands, etc. from a user. Suchinput or commands from input device 110 can be received at one or morecomputers 120 controlling operation of an amplifier system. Computer 120can also be in communication with power supplies for the amplifiersystems disclosed herein. For example, an AC (or DC) power supply 130can be controlled by computer 120 to deliver power to a powerdistributor 140.

The actual RF pulse amplified by the amplifier systems disclosed hereincan be generated from one or more RF FPGAs 140 that may be incommunication with computer 120. The RF FPGA generates the radiofrequency waveforms through a digital to analog converter (DAC). The DACcan have a digital input which can receive a stream of binary data thatrepresents the amplitude of the analog waveform that is output. Thisbinary data can be fed from computer memory where the binaryrepresentation of the samples of a waveform is stored or the binary datacan be generated by direct digital synthesizers (DDS). Some embodimentsmay include an array of DACs, each with its own binary stream. Thebinary stream can be controlled such that there is a phase offsetbetween the waves going to the different DACs to create a phased array.

RF FPGA 140 can provide RF signals to be amplified to an amplifierassembly 160 containing an arbitrary number of modular power amplifiers170. As described in further detail herein (e.g., with reference toFIGS. 7-9), such modular power amplifiers 170 can have an efficient 3Dconfiguration in the amplifier assembly, allowing for numerous technicalimprovements over conventional 2D amplifier systems. For example,cooling elements such as fans, heat sinks, etc. can be interspersedwithin the amplifier assembly between two or more of the modular poweramplifiers. The output of the modular power amplifiers can then bedelivered to an antenna array 190, which may be a part of anelectromagnetic pulse (EMP) system.

Examples of applications of the disclosed systems can include L-bandsystems capable of providing RF power output in the kilowatt range(e.g., 1 kW, 3 kW, 5 kW, 12 kW, 20 kW, etc.), though power output canvary with implementation and should not be limited to the examplesprovided. Similarly, the RF frequencies that may be utilized in thedisclosed systems need not be limited to L-band systems but may includeother frequencies as well, such as for example, S-band, K-band, etc.

A block diagram of an exemplary embodiment of a modular power amplifieris illustrated in FIG. 2. The modular power amplifier 170 can include anamplifier subsystem 210, which can receive RF input signal 220 andprovides an amplified RF output signal 230. Modular power amplifier 170can receive input driving/biasing power 240 at a power distributionmodule 250 and a power sequencer 270. These components can providedriving/biasing power for components of the modular power amplifier, asdescribed in further detail herein. In this way, an amplifier subsystem210 can be independently controlled to provide a particular RF outputsignal.

In some implementations, power distribution module may include a currentsensor 260 for monitoring of current output to the amplifier subsystem.The current sensor can then provide information to the power sequencerto adjust the power output from the power distribution module. Readingthe current of the power amps during operation alerts the system to thehealth of the power amplifiers, that the current is within the expectedrange. The current also enables the system to infer the temperature ofthe power amplifiers during operation since the current can rise for agiven power output as the temperature increases. The current sensor canalso be used to detect the set point of the power amplifiers prior tooperation; when the power amplifiers are off with no RF input, leakagecurrent can change as a function of the bias current being applied. Thisleakage current is read in the current sensor until the desired currentis detected, and thus gives the desired gate voltage set point thatshould be applied during operation. Without any loss of generality, theleakage current can be the bias current at the drain terminal of a FETamplifier. In one embodiment, the set point can be detectedautomatically prior to operation by slowly tuning the gate bias voltageuntil the ideal leakage current is detected. This voltage bias set pointcan be stored in memory and then during operation, applied when RF isapplied. If the current reading is either very low, indicating the poweramplifier is no longer pulling any power, or it is very high, indicatinga short, this indicates the power amplifier is no longer operational. Inthis way, the health of the power amplifier can be determined by readingthe current.

The power distribution module 250 can be configured to regulate anamount of power input (e.g., input power 240) to intermediate poweramplifier(s) (see, e.g., FIG. 3) of the amplifier subsystem.Specifically, the power distribution module 250 can receive power at agiven voltage, but provide power as needed (e.g., 50V, 65V, etc.) to theamplifier subsystem.

The power distribution module 250 provides several features. First itcan regulate the voltage received from the power supply to the poweramplifiers, such as a 50 volt supply to the drain of the gallium nitridepower amp transistors. In some embodiments, the power distribution unitcan provide DC to DC conversion of the voltage (e.g., acting as avoltage divider), such as if the incoming voltage from the power supplyis much higher than the power amplifier voltage. Second, powerdistribution module 250 can contain current sensor 260 where the powerdistribution unit 270 detects the current and reports the current backto the power sequencer for use in determining gate voltage bias setpoint and power amplifier health. Third, the power distribution unit 250can also provide a current limiter to limit the current to the poweramplifiers; this prevents the power amplifiers from blowing out shouldany errors occur such as a short, electromagnetic interference, loss ofpower, or other causes that would cause an incorrect gate bias voltage,and thus a dangerous over-current situation without a current limiter.In some embodiments, no more than 3 amps of current can go through thepower amplifiers before failure, so such a current limiter on the PDUcan be set to 3 amps. The power distribution unit consists of voltageregulators, analog to digital converters to read the current, as well asa current limiter circuit made of transistors, diodes and resistors.

In some implementations power sequencer 270 can be configured to controlthe timing of power delivery by the power distribution module. Forexample, the power sequencer can turn on or off the gate bias to theintermediate power amplifiers in synchronization with the RF input. Thishas the benefit of controlling the power and improve heat dissipation.The power sequencer circuit can include analog to digital converters(ADC) to read voltages and currents from power amplifier circuits,digital to analog converters (DAC) to apply voltages to power amplifiercircuits, such as gate bias voltages, as well as a processor such as amicrocontroller or field programmable gate array (FPGA). The powersequencer can have digital input pins for receiving commands when radiofrequency signals are being applied to the amplifier circuit. In thisway the power sequencer can apply a gate bias voltage to turn the poweramplifier “ON” just as RF signals are flowing through the poweramplifier and then remove the gate bias voltage to turn the poweramplifier “OFF” when no RF is flowing to save power. The power sequenceralso has a memory to store gate bias set points. In the preferredembodiment, the power sequencer can have a plurality of ADCs and DACs tocontrol multiple power amplifiers simultaneously.

Amplification of the RF input signal for a given modular power amplifieroccurs in one or more amplifier subsystems. As shown in FIG. 3a , anexample amplifier subsystem 210 (of modular power amplifier 170) canreceive RF input signal 220 at an optional preamplifier 310, which is inturn connected to bandpass filter 320. Bandpass filter 320 can limit thefrequency ranges of the signals passing through the system to aspecified bandwidth. Power amplifiers can provide higher power out andhigher gain when the bandwidth is smaller, so limiting bandwidth helpsincrease the gain and power of the amplifier system. Bandpass filter 320can also eliminate out-of-band spurs, harmonics, and other out-of-bandcontent. In other embodiments, bandpass filter 320 can instead be alow-pass filter or a high-pass filter to eliminate either high frequencycontent or low frequency content, respectively.

Amplifier subsystem 210 can also include, in some implementations, anumber of 90 degree hybrid blocks that can split or combine an RF signalby respectively adding or removing a 90 degree phase shift to the splitRF signal. Such RF signal components can be amplified individually andlater recombined. For example, a first 90 degree hybrid block 330 can beconfigured to receive an RF signal and output a split RF signal withcomponents having a 90 degree phase shift. As shown in FIG. 3a , 90degree hybrid block 330 can have RF i/o port 332, a “0 degree” port 334,and a “90 degree” port 336. The 90 degree hybrid block 330 receives theRF signal at the RF i/o port 332 and the split RF signal components arerespectively output through the 0 degree port 334 and the 90 degree port336. The 90 degree hybrid block 330 can also have a dump port 338 whichincludes a termination to dump mismatches.

A similar, or even identical, second 90 degree hybrid block 340 in theamplifier subsystem 210 can be configured to receive and combine thesplit RF signal by removing the 90 phase shift. As apparent from FIG. 3a, the unshifted RF signal component from the 0 degree port 334 goes intothe 90 degree input port 346. Similarly, the shifted RF signal componentfrom the 90 degree port 336 goes into the 0 degree input port 344. Thetwo signals can be combined and output through RF i/o port 342. 90degree hybrid block 340 can also have a dump port 348.

In some implementations, a high-power amplifier(s) 370 can be configuredto amplify at least one component of the split RF signal. Forimprovement of the amplification process, the bias for the high-poweramplifier 370 can be independently controlled via the power distributionmodule. The 90 degree hybrid combiner block 340 combines the twohigh-power amplifiers 370, to create a signal of double the power thatthe individual high-power amplifier 370, can produce, and transmits thisout of the output port of the hybrid power amp 230. In FIG. 3a , thepower distribution module 250 and power sequencer module 270, areconnected to the high-power amplifiers 370. In one embodiment, the powersequencer 270 can control the gate bias voltage to some or all of theamplifiers in the hybrid combination network such that they aresynchronized. In some embodiments, the power sequencer module 270 turnson the pre amplifiers 310 just before the high power amplifiers 370.

In other implementations, any/either/both 90 degree hybrid block caninclude a resistor configured to dissipate at least a portion of RFpower going through the 90 degree hybrid block when the RF power isabove a threshold. For example, such power dissipation can be used toreduce voltage standing wave ratio effects, thus improving therobustness of the amplifier system.

In many power amplifier systems the voltage standing wave ratio (VSWR isa measure of the efficiency of power transmitted/radiated out of theantenna. If power gets reflected back into the power amplifier system,this reduces the efficiency of the power amplifier system since not allof the input power is transmitted/radiated, and high power levels suchas with high power microwave and electromagnetic pulse applications,jamming, and high power radar, can damage the power amplifier system. Inimplementations using other means of power combining, such as usingGysel combiners or radial combiners, if one leg of the circuit fails dueto lack of protection, the entire 2-way, 4-way, or many-way combinedGysel or radial circuit can completely fail. In this way, the disclosedresistive dissipation provides a significant technical improvement overprior art systems. While one VSWR ratio that is usually acceptable is nomore than 2:1, 1.5:1 can be used for conservative systems. Powercombiners, such as the 90 degree hybrid approach discussed herein, candissipate VSWR levels at up to 10:1 (and potentially higher) and so isvery safe. VSWR depends on how well matched the resonant frequency ofthe power amplifier circuit is to the resonant frequency of the antenna.In some implementations, matching circuits can be created such thatmultiple frequencies are resonant in the power amplifier and the antennais broadband and covers many frequencies. As the frequency beingtransmitted differs from the resonant frequency the VSWR gets worse.Temperature variations can also degrade VSWR, other antenna elements inan array mutually coupling also degrades VSWR, anything that changes theimpedance of the circuit changes VSWR. Thus, VSWR can change verydynamically throughout the operation of a radio frequency system, andinstantaneously, it is possible for the VSWR to reach to very highlevels such as up to 10:1 (or more), illustrating the benefits of thedisclosed protective circuit.

FIGS. 3b-3d illustrate embodiments utilizing a differential antenna withcertain aspects of the present disclosure. FIG. 3b illustrates anexemplary embodiment of a power amplifier subsystem having a splitter380 configured to split an RF signal into a first RF component and asecond RF component. Such a splitter can be configured to split the RFsignal into two RF components of varying amplitude (e.g., a 50/50splitter, 70/30 splitter, etc.). The system can further include a firsthigh-power amplifier 370 configured to amplify and output the first RFcomponent and a second high-power amplifier 370 configured to amplifyand output the second RF component. The high-power amplifiers 370 inFIGS. 3b -d can be similar to other high-power amplifiers disclosedherein (e.g., high-power amplifier 370 as discussed with reference toFIG. 2).

Differential antenna 390 can have a first input operatively connected tothe first high-power amplifier to receive the first RF component and asecond input operatively connected to the second high-power amplifier toreceive the second RF component. In some embodiments this embodiment canreduce the number of (or eliminate entirely) the need for combiningcircuitry. In any of the disclosed implementations, the differentialantenna can be a high-impedance low-profile planar aperture 392. Anumber of such high-impedance, low-profile apertures 392 can beimplemented to form an array such as a connected dipole array 392 a, orits conjugate, a long-slot array antenna 392 b with orthogonalpolarization, as also illustrated in FIG. 3c . The connected dipolearray can include gaps having an approximately 300-ohm gap impedance(denoted by the arrows between various high-impedance, low-profileapertures 392). The long-slot array antenna 392 b can include an arrayof long slots excited at Nyquist interval by differential amplifiers.One advantage of such designs is eliminating the need of a conventionalbalun, and hence reducing the depth of the array antenna and thefront-end RF loss.

FIG. 3d illustrates how the previously disclosed amplifier subsystems210 can be utilized with a differential antenna. Here, a modular poweramplifier can have two power amplifier subsystems. Each power amplifiersubsystem can include a first 90 degree hybrid block configured toreceive an RF signal and output a split RF signal with components havinga 90 degree phase shift, a high-power amplifier configured to amplify atleast one of the components of the split RF signal, and a second 90degree hybrid block configured to receive, combine, and output the splitRF signal by removing the 90 degree phase shift. Similar to theimplementations in FIGS. 3 b,c, a differential antenna can be configuredto receive the output of the second 90 degree hybrid blocks of the twopower amplifier subsystems.

FIG. 4 illustrates how implementations of the present disclosure canallow the formation of a scaled power amplifier assembly 410 thatcombines multiple amplifier subsystems into a circuit equivalent to asingle amplifier subsystem but having increased gain. In the example ofFIG. 4, two power amplifier subsystems are shown, each including thefirst hybrid block and the second hybrid block. However, these poweramplifier subsystems 210 are integrated into scaled power amplifierassembly 410 where they have replaced the intermediate poweramplifier(s) in another power amplifier subsystem to form the scaledpower amplifier assembly 410. Such scaling can be extended to combineany number of power amplifier subsystems in a scaled power amplifierassembly (that may itself be made up of scaled power amplifierassemblies). While the implementation in FIG. 4 illustrates thecombination of three power amplifier subsystems, any number of poweramplifier subsystems can be utilized, for example, 2, 4, 5, 6, 10, etc.

In some embodiments, as shown in FIG. 5, the waveform generationcircuitry is embedded into the amplifier module 170 itself instead ofhaving a radio frequency signal be provided as input to the amplifiermodule. This is a distributed method of waveform generation where adigital command is provided to the input of the amplifier module 170instead of a radio frequency input. In some embodiments, the input 530can contain a digital message with a phase offset value, amplitude, anda frequency value to command the module to transmit an RF waveform withthe specified waveform and phase offset. These commands can also becomemore complex such as a series of commands such that the amplitude, phaseoffset and frequency vary as a function of time. A clock sync signal 520can be input that originates at a common source such as a master clockwith the purpose of synchronizing multiple modular power amplifiers sothey can transmit commands phase-coherently to one another. This clocksync pulse can be used to align the digital clocks within the module tothe sync pulse. The phase locked loop (PLL) sync clock 560 can be inputinto a PLL circuit 570 such that the PLL circuit 570 provides theclocking to the rest of the module and synchronizes with the PLL input560 as another mechanism to synchronize the clocks. In some embodiments,an FPGA 510 and digital to analog converter 540 receive digital commandsand the clock synchronization signal and translate the digital commandsinto a radio frequency signal for the power amplifier subsystem. Inother embodiments, a direct digital synthesizer (DDS) chip is usedinstead of an FPGA and a DAC. In some embodiments, the RF signalgenerated from the DAC 540 is a sufficiently high frequency and isconverted to the desired RF frequency by the DAC and input into theamplifier module 210. In other embodiments the DAC 540 outputs anintermediate frequency (IF) which is upconverted using a mixer subsystem550 to the final desired frequency. There are multiple ways the mixingcan be done, such as homodyne mixing, heterodyne mixing, etc. Asillustrated in the example of FIG. 6, the modular aspects of thedisclosed amplifier systems can be utilized in a parallel configurationto provide high-gain amplification of an RF input signal 610. In someimplementations, a driver amplifier 620 can receive the RF input signal610 and provide an RF output (e.g., approximately 50 W) to a powerdivider 630. The power divider 630 can be coupled to modular poweramplifiers 170 arranged in parallel and configured to receive andamplify respective RF signals from the power divider 630.Implementations of the disclosed amplifier systems can then result in RFoutput power of at least 12 kW (e.g., from the combined output of four 3kW amplified RF signals from modular power amplifiers 170). Optionally,the power divider can receive control signals 640 to control thesplitting of the RF input signal. Also, the power divider can havevarious power channels 650, including inputs and/or returns for ACand/or DC power. The power divider 630 can be a Wilkinson power divideror other circuit that divides the incoming signal power evenly betweenmultiple output channels.

The illustrated examples of modular power amplifiers 170 can besubstantially similar to any of those described throughout the presentdisclosure. However, also shown in the implementation of FIG. 6 arecontrol channels 642 (e.g., for providing control signals to the modularpower amplifier 170 and its various components), power channels 652(e.g., for providing power to various modular power amplifiercomponents), and RF channels (e.g., for directing RF between variouspower amplifier components).

In some implementations, illustrated for example in FIG. 6, a high-powercombiner assembly 660 can be coupled to the modular power amplifiers 170and configured to combine respective RF output signals from the modularpower amplifiers 170. The power combiner assembly can be a Wilkinsonpower combiner, radial power combiner, or Gysel power combiner. In thisway, a single, greatly amplified RF output signal 614 can be generated.

As used herein, the term “parallel” can mean geometrically parallel(e.g., disposed in parallel planes) or electrically parallel (e.g., notin series). For example, the block diagram illustrated in FIG. 6 showshow the disclosed system has aspects that are electrically parallel, butnot necessarily geometrically parallel. An example implementation havingaspects that are specifically not geometrically parallel is shown inFIG. 7, below, where some of the generally planar amplifier circuits areoriented orthogonally to each other.

FIG. 7 illustrates an implementation with a 3D configuration ofamplifiers having the benefits of, for example, reduced electromagneticinterference, efficient use of space, and access to cooling mechanisms.As shown in FIG. 7 one implementation of a three-dimensional poweramplifier 700 can include a first modular power amplifier 710 configuredto receive a first RF signal and output a first amplified RF signal. Thethree-dimensional modular power amplifier 700 can also have a secondmodular power amplifier 730 configured to receive a second RF signal andoutput a second amplified RF signal. In some embodiments, RF inputsignals can be received by 90 degree hybrids (which may be similar tothe 90 degree hybrid 330 in FIG. 3a ). RF signals can be similarly powercombined into another 90 degree hybrid output block (which may besimilar to the 90 degree hybrid 340 in FIG. 3a ). Variousimplementations can have the second high-power amplifier 730 can have adifferent orientation than the first high-power amplifier 710. Thus, thedifferent orientations can cause a reduction in electromagneticinterference between the first high-power amplifier and the secondhigh-power amplifier. Also, antenna 770, for three-dimensional poweramplifier 700, can optionally be part of antenna array 190 depicted inthe implementation of FIG. 1.

As used herein, the term “orientation” refers to an orientation of thehigh-power amplifier in 3D space. For example, the high-power amplifiermay be a somewhat planar circuit oriented generally horizontally. Asdescribed above, a different high-power amplifier may have a differentorientation (e.g., generally vertically). Because such high-poweramplifiers may generally be of substantially similar construction, itwould be understood by a person of skill what it means to have two highpower amplifiers have different orientations. Furthermore, while thepresent disclosure contemplates that high-power amplifiers may havedifferent orientations, this can also include other circuitry (besidesthe high-power amplifiers) such as the 90° hybrids, splitters, FPGAs,etc. Any combination of the components disclosed herein that areassociated with a given high-power amplifier can thus have a particularorientation which may be different than any other combination ofcomponents associated with another high-power amplifier.

Some implementations can include the first high-power amplifier and/orthe second high-power amplifier being of generally planar constructionand the generally planar amplifiers can have different orientations.Accordingly, in some implementations, the first high-power amplifier andthe second high-power amplifier can be constructed on printed circuitboards and disposed to have the different orientations.

The present disclosure contemplates the non-parallel orientations ofthese high-power amplifiers can mitigate electromagnetic interferencebetween the amplifiers by, for example, reducing interference(constructive or destructive). When the present disclosure notes thattwo amplifiers are “not in the same plane,” this means that they arenon-coplanar but may be in parallel planes. When high-power amplifiers(or other circuitry) has the same orientation, metal shielding can beincluded around one or more locations to mitigate EMI. In someembodiments, some portions of the disclosed system can have high-poweramplifiers parallel to each other, either vertically or horizontally.This can be in combination with any non-parallel arrangements ofcircuits, as discussed below and elsewhere herein.

As shown in FIG. 7, the different orientations can have an angle of 90degrees between them to form a portion of a square (or rectangular)distribution of high-power amplifiers. Orienting at a 90 degrees anglearound a heat sink, (such as a piece of metal or a fan) also helps toease thermal constraints and remove heat.

In other implementations, the different orientations can have an angleof 120 degrees between them to form a portion of a hexagonaldistribution of modular power amplifiers. In yet other implementations,the different orientations can have an angle of 60 degrees between themto form a portion of a triangular distribution of modular poweramplifiers. In general, any geometric distribution of modular poweramplifiers is contemplated, further including parallelograms or otherpolygonal or irregular shapes. In this way, most generally, the presentdisclosure contemplates that at least two of the power amplifiers maynot be geometrically parallel, for at least the above-described benefitsof heat removal and reduction of EMI.

As shown in FIG. 7, in other implementations, there can be a thirdhigh-power amplifier having an orientation substantially perpendicularto the first high-power amplifier and a fourth high-power amplifierhaving an orientation substantially perpendicular to the secondhigh-power amplifier. Such a configuration is similar to the squaredistribution described above, but also includes parallelogram-shapeddistributions.

As discussed, the disclosed three-dimensional power amplifier hasseveral technical advantages, including improved cooling due to theability to of, for example, generally planar modular power amplifiers,to have their planes facing a cooling element. This can expose anincreased surface area to a cooling element and thus improve cooling.Cooling elements can include, for example, a heat sinks, fans, etc. withnumber and any sort of cooling element implemented. As shown in FIG. 7,there can be a cooling component (e.g., heat sink 750) located proximateto the first high-power amplifier or the second high-power amplifier.Also, a fan 760 can be included to provide direct air cooling over theamplifier circuitry and heat sinks.

The amplifier designs contemplated herein provide improved mitigation ofelectromagnetic interference. In some implementations, this can includeproviding electromagnetic shielding between the first high-poweramplifier and the second high-power amplifier. Such electromagneticshielding can include, for example, Faraday cages, RF absorptive foam,RF reflective materials, etc. In some implementations, such shieldingcan be located around or between modular power amplifiers.

Some implementations can provide further mitigation by virtue of theseparation between any adjacent parallel modular power amplifiers. Forexample, the first high-power amplifier and the second high-poweramplifier can be configured to receive the first RF signal and thesecond RF signal, both signals having a wavelength, and the firsthigh-power amplifier and the second high-power amplifier are separatedby at least approximately half of the wavelength. In some embodiments,the amplifiers can be separated by less than half a wavelength. Sucharrays can be challenging to integrate from a mechanical packagingstandpoint due to the tight spacing, but can provide higher power perunit area. In other embodiments, the amplifier modules are separated bymore than half a wavelength. Any spacing more than half a wavelength cancause a smaller grating-lobe free field of regard. At a half-wavelengthspacing, a beam can be scanned over a 180 degree field of regard fromthe array. As the spacing increases up to lambda (the wavelength), thegrating lobe free field of regard is reduced. In one a 0.7 lambdaspacing can be used, which allows more space to fit the modules but alsoallows a larger area for the antenna array. As the gain is related tothe area of the antenna array, moving out the modules enables highergain. Separations can include, for example, 5 inches, which can beappropriate for some L-band phased array application. Other separationsare contemplated, based on the wavelength of the RF being amplified, asdiscussed above, or other separations that act to mitigate interference.In some implementations, the wavelength used is the wavelength of thehighest frequency (or smallest wavelength) being used in the design.

As shown in FIG. 8, an exemplary embodiment of a modular power amplifier800 can include many of the components disclosed herein, allowing, forexample, efficient replacement of damaged or upgraded modules. Forexample, the modular power amplifier 800 can include an RF input port810, a power input port 820, a digital control port 830, and an RFoutput port 840. Such ports simplify the connections needed to operateand maintain the amplifier system.

FIG. 9 illustrates an exemplary embodiment of a rack 910 suitable forholding one or more modular power amplifiers 800. The rack 910 can be alattice-shaped structure configured to receive any number of modularpower amplifiers. Rack 910 can include guides and spacers betweeninstalled modular power amplifiers to enable the proper alignment andspacing to enable various improves disclosed herein, such as wavelengthseparations between amplifiers or incorporating shielding into thestructure of the rack for further EMI mitigation. For example, oneimplementation of the disclosed systems can include those having an RFgenerator configured to generate RF signals at a particular wavelength.The system can include amplifiers (such as may be held in rack 910) thatcan be configured to receive and amplify the RF signals. As mentionedpreviously, certain implementations can have the amplifiers separatedfrom each other by at least approximately half of the wavelength toreduce EMI. As used herein, the term “approximately half of thewavelength,” or the like, is understood to allow for some variationaround the half-wavelength, but which still effectively mitigates EMIbetween adjacent amplifier components. For example, the separation canvary by up to 35% around the half-wavelength and still be consideredwithin the scope of the present disclosure. As described in greaterdetail below, some implementations of the disclosed systems can includea power management system configured to control one or more of theamplifiers based on information received from various sensing circuitsmonitoring RF signal generation.

In some implementations, the separation between individual racks 910comprising amplifiers can be spaced apart by a separation distance thatis in a range between approximately 0.2 times the wavelength and about10.0 times the wavelength of the signal amplified by the amplifiers. Forexample, the separation between individual racks 910 can beapproximately 0.25 times the wavelength, 0.3 times the wavelength, 0.4times the wavelength, 0.5 times the wavelength, 0.6 times thewavelength, 0.7 times the wavelength, 1.0 times the wavelength, 1.5times the wavelength, 2.0 times the wavelength, 2.5 times thewavelength, 3.0 times the wavelength, 4.0 times the wavelength, 5.0times the wavelength, 7.0 times the wavelength, 10.0 times thewavelength, or any separation therebetween. In other implementations,separations can be between approximately 2-18 inches or 3-7 inches. Asdiscussed above, increasing the spacing separation between individualracks 910 can allow integration of antennas with the larger areas (e.g.,horn antenna designs) with amplifiers which can provide larger antennagain. Such systems can be useful to provide higher power with smallernumber of antenna elements.

FIG. 10 illustrates an implementation similar to system 100 of FIG. 1,but with additional details provided for a number of components. Forexample, target detector 1010 can be similar to user input device 110,which was previously described as usable for selecting targets of theantenna array. Similarly, computer 1020 can be similar to computer 120,antenna 1090 (having individual antennas 1090_1 to 1090_N) can besimilar to antenna array 190 and so on. Also, RF generator 1050 can besimilar to RF FPGA 150, but with additional details shown in thisimplementation, such as including a direct digital synthesis (DDS) RFgenerator 1052, digital to analog convertors (DACs) 1054_1 to 1054_N, Fconnectors 1056_1 to 1056_N, and gate array 1058. Computer 1020 can besimilar to mission computer 120, but herein further including CPU 1022in communication with target classifier 1024, waveform LUT 1026,waveform selector 1028, and system power monitor 1029.

As used herein the notation “X_1 to X_N” describes a collection ofelements X of any size 1 to N, including only 1. For clarity, in manylocations only a reference is given to a single element (e.g., 1090_1),but such references should be understood to refer to any element in thecollection and not necessarily specifically the first one.

The exemplary embodiment 1000 is illustrated as being augmented with aplurality of power management systems 1040_1 to 1040_N configured toprovide the required voltages and currents to efficiently operate theamplifiers in the amplifier chains 1070_1 to 1070_N. In variousimplementations, the power management systems 1040_1 to 1040_N cancomprise or be associated with a power distributing/sequencing systemsimilar to the power sequencer 270. Individual power management systems1040_1 to 1040_N can be configured to: (i) in response to receiving asignal from the RF generator 1050 provide appropriate bias voltagesand/or currents to turn on the amplifiers in the corresponding amplifierchains 1070_1 to 1070_N prior to/synchronously with the arrival of theRF signal from the RF generator 1050, (ii) change the bias voltages andcurrents to the amplifiers based on a sensed characteristic (e.g.,temperature, gate current or drain current), and/or (iii) reduce thebias voltages and currents to turn-off the amplifiers in thecorresponding amplifier chains 1070_1 to 1070_N in response to absenceof signal to be amplified or a sensed characteristic (e.g., temperature,gate current or drain current) being outside a range of values. In someimplementations, the individual power management systems can beconfigured to automatically determine the voltages and currents requiredto turn-on/turn-off the amplifiers in the corresponding amplifier chains1070_1 to 1070_N. In some implementations, the automatic determinationcan be made using a calibration routine performed prior to using thesystems. In some implementations, the power management system can beconfigured to access computer memory to obtain historical data storedfrom prior operations of the system. The automatic determination canthen be based at least partially on the historical data.

As discussed above, the plurality of power management systems 1040_1 and1040_N can comprise sensors (e.g., current sensors) that can sensecurrent values (e.g., drain and/or gate current values) of theindividual amplifiers in the amplifier chains 1070_1 to 1070_N. Thesensors can be similar to sensor 260 discussed above. The powermanagement systems 1040_1 and 1040_N can be configured to sense thecurrent values of the individual amplifiers in the amplifier chains1070_1 to 1070_N intermittently (e.g., periodically). In someimplementations, the power management systems 1040_1 and 1040_N can beconfigured to sense the current values of the individual amplifiers inthe amplifier chains 1070_1 to 1070_N continuously. In variousimplementations, the output from the current sensor can be sampled usingan analog to digital converter (ADC) and averaged over a number ofsamples (e.g., 128 samples, 512 samples, etc.) to obtain the sensedcurrent value.

The sensed current value can be analyzed by the power management systems1040_1 to 1040_N to determine an operational or a physicalcharacteristic (e.g., temperature) of the individual amplifier. Forexample, a sensed current value above a first threshold current valuewhen the amplifier is not turned on can be indicative of a defect in theamplifier or a defect in the circuit board on which the amplifier ismounted. As another example, a sensed current value above a secondthreshold current value when the amplifier is turned on but no signal tobe amplified is provided to the input can be indicative of a defect inthe amplifier or a rise in the temperature of the amplifier. As yetanother example, a sensed current value above a third threshold currentvalue when the amplifier is turned on and a signal to be amplified isprovided to the input can be indicative of a defect in the amplifier ora rise in the temperature of the amplifier. Accordingly, the powermanagement systems 1040_1 to 1040_N can be configured to compareindividual amplifier current values to target amplifier current valuesto identify an amplifier state error. In response to determining thatthe amplifier current value of a particular amplifier has deviated froma target amplifier current value (e.g., first, second or third thresholdvalues discussed above), the power management system controlling thatparticular amplifier is configured to determine the amount by whichvalues of the voltages/current provided to the amplifier should beoffset to achieve efficient operation of the amplifier and provide thatoffset value. In various implementations, one or more of tasks ofcorrelating the sensed current values to a physical characteristic ofthe amplifier or determining the amount by which values of thevoltages/current provided to the amplifier should be offset by toachieve efficient operation of the amplifier can be performed by thecomputer 1020 instead of the power management systems 1040_1 to 1040_N.

The target amplifier current values may be based upon several factorsfor optimal system operation. For example, the target amplifier currentvalues may be calibration amplifier current values for specifiedtemperatures. The target amplifier current values may be calibrationamplifier current values to compensate for amplifier manufacturingprocess variations. The target amplifier current values may becalibration amplifier current values to compensate for voltagevariations. The target amplifier current values may be calibrationamplifier current values to compensate for radio frequency phasevariations. The target amplifier current values may be historicalperformance amplifier current values. The historical performanceamplifier current values may be used to identify amplifier degradationover time.

FIG. 11 illustrates an implementation of a power management system(e.g., 1040_1, but may apply to any of the power management systems).The power management system 1040_1 can include various functionalsub-systems, such as an electronic processing system 1111, a controlsystem 1115, a memory (not shown), a sensing system 1121, a poweradapting system 1123, and an input/output system 1119. The variousfunctional sub-systems can be integrated in a single housing or inseparate housings. In implementations where the different functionalsub-systems are integrated in separate housings, the separate housingscan include processing electronics and communication systems tocommunicate and function properly. For example, in some implementations,the power adapting system 1123 and the sensing system 1115 can beintegrated in a separate housing. In such implementations, theelectronic processing system 1111 in cooperation with the control system1115 and the memory can provide signals to the power adapting system1123 to turn-on/turn-off the biasing voltages and currents to theamplifiers in response to receiving a signal from the RF generator 1050indicating the start/end of the RF signal and/or receiving informationfrom the sensors that one or more sensed parameters are out of a rangeof values.

The power management system 1040_1 can be implemented in, for example, afield programmable gate array (FPGA) or in a 5mm x 5mm applicationspecific integrated circuit (ASIC). The power management system 1040_1can be configured to obtain information about the signals to beamplified and monitor various currents and voltages of the amplifier tooptimize and control operating currents and voltages of the amplifier.The power management system 1040_1 can obtain the information about thesignals to be amplified and the currents/voltages at various terminalsof the amplifier in real-time or substantially in real-time. Forexample, the power management system 1040_1 can obtain the informationabout the signals to be amplified and the currents/voltages at variousterminals of the amplifier in a time interval less than about 1 second,in a time interval greater than or equal to about 1 millisecond and lessthan about 1 second, in a time interval greater than or equal to about 1second and less than about 10 seconds, in a time interval greater thanor equal to about 10 seconds and less than about 30 seconds, in a timeinterval greater than or equal to about 30 seconds and less than about 1minute and/or in a range defined by any of these values.

The power management system 1040_1 can provide several benefitsincluding but not limited to increasing/optimizing power efficiency fora desired performance criterion. For example, consider that an amplifierin the amplifier chain 1070_1 being controlled by the power managementsystem 1040_1 is operated in a high gain regime to provide a certainamount of RF output power. The power efficiency of that amplifier can behigher than a similar amplifier that is operated in a high gain regimeto provide the same amount of RF output power but is not controlled bythe power management system 1040_1. As another example, consider that anamplifier in the amplifier chain 1070_1 controlled by the powermanagement system 1040_1 is operated to provide a certain amount of gainand linearity. The power efficiency of that amplifier can be higher thana similar amplifier that is operated to provide the same amount of gainand linearity but is not controlled by the power management system1040_1. The use of the power management system 1040_1 can also reducedirect current (DC) power consumption during operation of an amplifieras compared to direct current (DC) power consumption by an amplifierdriven without a power management system 1040_1. The power managementsystem 1040_1 can improve linearity of an amplifier, help in automaticcalibration of an amplifier over temperature, voltage and processvariations, and/or have the ability to auto calibrate for phased arrayapplications.

The electronic processing system 1111 can comprise a hardware processorthat is configured to execute instructions stored in the memory whichwill cause the power management system 1040_1 to perform a variety offunctions including, but not limited to, turning on/off or reducevoltages/currents provided to various terminals of an amplifier inresponse to detecting that the signal to be amplified is turned on/offor sensing individual amplifier current values and change the values ofdifferent voltages and currents in response to the deviations of thesensed current values from target values.

The input/output system 1119 can be configured to provide wired/wirelessconnection with external devices and systems. For example, theinput/output system 1119 can comprise an Ethernet port (e.g., a GigabitEthernet (GbE) connector) that provides connection to the computer 1020and/or a router, one or more connectors that provide connection to theRF signal generator 1050, a connector that provides connection with anexternal power supply, a plurality of connectors that providevoltages/currents to one or more amplifiers, a plurality of connectorsthat can receive voltage/current information from the one or moreamplifiers, and connectors that provide connection with a user interface(e.g., a display device). In various implementations, the input/outputsystem 1119 can comprise a command-and-control link to receive messagesfrom the RF generator 1050 and/or computer 1020.

The input/output system 1119 can be configured to receive, as input, asignal/trigger/information from the RF signal generator 1050 and use theinformation from this input to determine the voltages and current for anamplifier in the amplifier chain 1070_1. As discussed above, the inputreceived from the RF signal generator can be a trigger that conveysinformation that the RF signal will be turning on and causes the powermanagement system 1040_1 to start the power sequencing process andprovide appropriate voltages and/or currents to bias the amplifiers inthe corresponding amplifier chain 1070_1 prior to the arrival of the RFsignal. For example, the input from the RF signal generator can be apulse enable signal which is high when the RF signal is on and low whenthe RF signal is off. In various implementations, the input from the RFsignal generator 1050 can be representative of the waveform being outputby the DAC 1054_1 of the RF generator 1050. In some implementations, theinput can include instructions and/or settings to power on the powermanagement system 1040_1, to power up an amplifier in the amplifierchain 1070_1, and other data to operate the power management system1040_1 and an amplifier in the amplifier chain 1070_1.

The input/output system 1119 can comprise a communication systemconfigured to communicate with external devices and systems. Forexample, the input/output system 1119 can comprise Ethernet connectivityto send information including but not limited to amplifier healthinformation, and efficiency statistics to the computer 1020. Ethernetconnectivity can also be utilized in synchronizing an array of powermanagement systems in phased array applications. The input/output system1119 can include connectors that can be configured to providevoltages/currents to at least one terminal of an amplifier in theamplifier chain 1070_1 to 1070_N. For example, the voltages and currentsrequired to bias at least one of the gate, source and/or drain terminalof an amplifier in the amplifier chain 1070_1 can be provided throughthe output ports of the power management system 1040_1. The powermanagement system 1040_1 can be configured to provide bias voltageand/or current to a plurality of amplifiers. For example, the powermanagement system 1040_1 can be configured to provide bias voltageand/or current to two, four, six or more amplifiers.

The sensing system 1121 can be configured to sense current values at oneor more terminals of the amplifier as discussed above. In variousimplementations, the sensing system 1121 comprises at least one currentsensor and an analog to digital converter configured to sample andaverage the output of the current sensor to obtain a sensed currentvalue. In various implementations, the current sensor need not beintegrated with the other components of the sensing system 1121 and/orthe other sub-systems of the power management system 1040_1. Instead,the current sensor can be integrated with the amplifier. The number ofcurrent sensors can vary based on the number of amplifiers beingcontrolled by the power management system 1040_1 and the number ofcurrents that are being monitored. For example, if the power managementsystem 1040_1 is configured to control four distinct amplifiers and itis desired to monitor the drain current of each of the four separateamplifiers, then the power management system 1040_1 can include fourcurrent sensors configured to monitor the drain current of each of thefour distinct amplifiers.

The power adapting system 1123 can be configured to convert power froman external power supply 1125 (e.g., an AC power line, a battery source,a generator, etc.) to voltage and current waveforms required foroperating the amplifiers being controlled by the power management system1040_1. For example, in various implementations, the power adaptingsystem 1123 is configured to convert a 60V DC bus and generateappropriate voltage and current inputs for the various terminals of theamplifier. In some implementations, the power adapting system 1123 maybe configured to convert an incoming AC power line to DC power (e.g., toabout +80 Volts DC). The power adapting system 1123 is configured tostep down the converted DC voltage to appropriate voltages for theamplifier (e.g., in a voltage range between about +45 Volts and +70Volts high voltage Gallium Nitride power amplifiers) through DC/DCconverters. The stepped down voltages are provided to the variousterminals of the amplifier (e.g., gate, drain, and/or source) in asequence as discussed above in response to receiving a signal from theRF signal generator 1050 and/or the computer 1020 that the signal to beamplified is turned on/being turned on. In various implementations, thepower adapting system 1123 comprises a “power gating” feature where thevoltage to the gate terminal of the amplifier is raised and lowered toturn on/turn off the power amplifier in response to the turning on andturning off the RF signal. For example, in an implementation of theamplifier chain 1070_1 comprising a GaN power amplifier, the powermanagement system 1040_1 can toggle the gate voltage between about −5V(pinch off or turn off) and about −2.5V (saturation or turn on) at afrequency greater than or equal to 1 kHz and less than or equal to about500 MHz. For example, the gate voltage can be toggled between pinch offand saturation at a rate greater than or equal to about 10 MHz and lessthan or equal to about 100 MHz. Without any loss of generality, thepower management system 1040_1 can be configured to turn-on and turn-offthe amplifier in between pulses of a pulsed waveform. This canadvantageously allow heat to dissipate from the amplifier in betweenpulses thereby reducing the rate at which the amplifier heats up andincrease lifetime. Turning on and off the amplifier in between pulses ofa pulsed waveform can also advantageously increase the power efficiencyof the amplifier.

The control system 1115 can be configured to control and/or managevarious functions and processes of the power management system 1040_1.For example, the control system 1115 independently or in co-operationwith the computer 1020 and/or the RF generator 1050 can control theorder in which the voltage and current levels at various terminals ofthe amplifier are changed to power up/down the amplifier. As anotherexample, the control system 1115 independently or in co-operation withthe computer 1020 and/or the RF generator 1050 can control the raisingand lowering of the voltage/current levels at the gate terminal of theamplifier synchronously with the incoming signal to be amplified. As yetanother example, the control system 1115 independently or inco-operation with the computer 1020 and/or the RF generator 1050 cancontrol the timing of turning on the various amplifiers in the amplifierchains 1070_1 to 1070_N.

FIG. 12 is a schematic illustration including an amplifier 1228 that ispart of amplifier chain 1070_1 controlled by the power management system1040_1. As discussed above, the power management system 1040_1 can beconfigured to use the information (RF data 1210) about the signal to beamplified to adjust/tune bias voltages and currents required to powerup/down one or more amplifiers in the amplifier chain 1070_1 to improvevarious figures of merit (e.g., power efficiency, linearity, etc.) ofthe one or more amplifiers in the amplifier chain 1070_1. The amplifier1228 is a FET amplifier having a gate terminal 1230 and a drain terminal1232. As discussed above, the power management system 1040_1 isconfigured to provide voltage/current to the gate terminal 1230 and thedrain terminal 1232 of the amplifier as well as adjust thevoltage/current levels at the gate terminal 1230 and the drain terminal1232 based on information regarding the incoming signal and/orinformation regarding the temperature and other physical characteristicsof the amplifier 1228.

The signal to be amplified can be input to the gate terminal 1230 via aninput matching circuit 1234. The amplified signal can be output from thedrain terminal 1232 via an output matching circuit 1236. To ease theburden on the power adapting system 1223, one or more storage capacitors1238 are placed near the drain terminal 1232 of the amplifier 1228. Theillustrated implementation comprises a single storage capacitor 1238.The storage capacitors can have a capacitance value between about 700microfarads and 2000 microfarads. The presence of the storage capacitors1238 are advantageous in high power applications and/or applications inwhich the signal has a high duty cycle. In implementations comprising aplurality of capacitors, the plurality of capacitors in arranged inparallel. As discussed above, the power management system 1040_1comprises a plurality of current sensors 1240 and 1242 that areconfigured to sense/monitor drain and gate current respectively. Thecurrent sensor 1240 configured to monitor/sense drain current can bepositioned downstream of the storage capacitor 1238 as shown in theillustrated embodiment or upstream of the storage capacitor 1238 inother embodiments. The power management system 1040_1 can also comprisea temperature sensor 1244 configured to sense/monitor the ambienttemperature in the vicinity of the amplifier 1228. For example, thetemperature sensor 1244 can be configured to measure the temperature ofthe circuit board on which the amplifier 1228 is mounted.

The power management system 1040_1 can be configured to protect theamplifiers from damage. The power management system 1040_1 can beconfigured to monitor voltages and/or currents at various terminals ofthe amplifier and turn-off the amplifier if the current and/or voltageexceeds a certain limit. For example, the power management system 1040_1can be configured to turn off an amplifier in the amplifier chain 1070_1if the drain current of that amplifier exceeds a preset threshold. Thethreshold drain current for the various amplifiers controlled by thepower management system 1040_1 can be programmed and stored in a memoryaccessible by the power management system 1040_1. The threshold draincurrent can be different when the RF signal is on and off. As anotherexample, the power management system 1040_1 is configured to turn-offthe amplifier if the rate of increase of the drain current of anamplifier during power up sequence is below a threshold rate. Thethreshold rate of increase of the drain current for the variousamplifiers controlled by the power management system 1040_1 can beprogrammed and stored in a memory accessible by the power managementsystem 1040_1. In various implementations, the power management system1040_1 can be configured to monitor the duration of time an amplifier ison and turn off the amplifier if an amplifier is on for an amount timegreater than a preset amount of time even if the RF signal is on. Thepreset amount of time can be programmed and stored in a memoryaccessible by the power management system 1040_1. In variousimplementations, an input switch can be provided in the input signalpath of the amplifier. In such implementations, the power managementsystem 1040_1 can be configured to open the input switch and disconnectthe RF signal from the input to the amplifier if the voltage, currentand/or duration of time the amplifier is on exceeds a limit. In variousimplementations, a load switch can be provided in the drain path of theamplifier. In such implementations, the load switch can be opened todisconnect the drain and prevent damage to the amplifier if the draincurrent exceeds a limit.

The bias voltage/current of an amplifier (e.g., a GaN power amplifier)that optimizes the power efficiency of amplifier can vary based on thedevice temperature. Thus, the power efficiency of an amplifier candegrade from an optimum power efficiency as the temperature of theamplifier changes. Without relying on any particular theory, thetemperature of the amplifier can increase over the duration of time thatthe amplifier is in use. Thus, it is advantageous to intermittentlyobtain a measurement/estimate of the temperature of the amplifier duringuse and adjust the bias voltage/current to optimize power efficiencyand/or other figures of merit of the amplifier. The bias voltage/currentthat optimizes power efficiency can also be affected due to degradationin the device performance due to defects during manufacturing, aging ora defect in the circuitry surrounding the amplifier.

FIG. 13 illustrates an exemplary correlation between the drain currentand the device temperature for an implementation of a FET amplifier.While the temperature sensor 1244 in FIG. 12 may provide informationregarding the ambient temperature around the amplifier 1228. In manyimplementations, it may not be practical to use a temperature sensor toobtain an estimate of the device temperature of the amplifier 1228.However, the drain current can be correlated to the device temperatureof the amplifier 1228 and can be used to measure the device temperatureof the amplifier 1228. In the example of FIG. 13, the embodiment of theFET amplifier is biased at a gate voltage of −2.763V and the draincurrent changes from about a few milliamps to about 225 milliamps as thetemperature of the embodiment of the FET amplifier rises from about 40degrees Celsius to about 85 degrees Celsius. The variation of the draincurrent versus temperature can be different when the biasing gatevoltage is changed.

The drain current can also provide an indication of a degradation in theperformance of the amplifier 1228 as a result of defects due tomanufacturing/aging or a defect in the circuitry surrounding theamplifier. Thus, adjusting the biasing voltages/currents based onmeasuring the drain current can advantageously aid in optimizing powerefficiency and other figures of merit of the amplifier 1228. The draincurrent can be obtained under DC bias condition when the signal to beamplified is absent, when the signal to be amplified is present and/orin between signal pulses. For example, in some implementations, thesensor 1240 can be configured to sense the drain current continuously oralmost continuously. As discussed above, analog-to-digital converters inthe power management system 1040_1 sample the sensed current. Ameasurement of the drain current is obtained by averaging over aplurality of samples of the sensed current. The electronic processingsystem 1111 can be configured to correlate the measured drain current tothe device temperature of the amplifier 1228. The electronic processingsystem 1111 can be configured to correlate the measured drain current tothe device temperature of the amplifier 1228 using algorithms and/orlook-up-tables (LUTs).

As the device temperature of the amplifier 1228 changes, the biasinggate voltage that would achieve power efficient operation can change.Accordingly, in many implementations, the electronic processing system811 of the power management system 1040_1 can be further configured tochange the biasing gate voltage based on the device temperature obtainedfrom the measured gate current. The electronic processing system 811 canbe configured to obtain the amount by which the gate voltage should bechanged (also referred to herein as gate offset voltage) usingalgorithms and/or look-up-tables (LUTs). The gate offset voltage can bein a range between about 1 mV and about 500 mV. In variousimplementations, the signal to be amplified is turned off beforechanging the gate voltage by the offset amount. In some implementationswherein the signal to be amplified comprises pulses, the gate voltage ischanged by the offset amount in the time interval between pulses. Insome implementations, the gate voltage is changed by the offset amountwhen the signal to be amplified is on.

FIG. 14 illustrates an exemplary reduction in temperature due to anadjustment in gate bias voltage. In addition to optimizing powerefficiency based on device temperature and/or achieving a desired powerefficiency at different temperatures, the power management system 1040_1can also help in preventing a rapid increase in the device temperatureby adjusting the gate bias voltage as the drain current changes tomaintain an optimal gain and/or power efficiency. As depicted in FIG.14, an implementation of an amplifier controlled by the power managementsystem 1040_1 can be operated in two conditions. In both the operatingconditions, the bias voltage to the gate terminal of the amplifier canbe turned on a short time before a RF signal is input to the amplifierand turned off a short time after the RF signal is turned off. Forexample, the gate bias voltage can be turned on/off at a duty cycle of1%. However, in the first operating condition the gate bias voltage ismaintained at a constant voltage, while in the second operatingcondition the gate bias voltage is changed as the drain current changes.

The effect of changing the gate bias voltage with the drain current notonly increases/maximizes the gain provided by the amplifier over timebut also prevents a rapid increase in the temperature of the amplifierover time. This is illustrated by curve 1402 exhibiting a rapid rise inthe temperature of an amplifier over time when operated in the firstoperating condition and a curve 1404 exhibiting a gradual rise in thedevice temperature of an amplifier over time when operated in the secondoperating condition. As noted from curve 1402, the temperature of theamplifier can increase from about 22 degrees Celsius to about 48 degreesCelsius in less than 500 seconds when the amplifier is operated in thefirst operating condition. In contrast, the temperature of the amplifierincreases gradually from about 22 degrees Celsius to about 32 degreesCelsius in about 3000 seconds when the amplifier is operated in thesecond operating condition.

Accordingly, systems including amplifiers controlled by a powermanagement system 1040_1 that is configured to turn on/off the amplifierbased on the presence/absence of the signal to be amplified as well asadjust the gate bias voltage based on the monitored drain current canoperate efficiently and/or provide nearly constant gain at a wide rangeof temperatures (e.g., between about −20 degrees Celsius and about 90degrees Celsius). Such systems can also operate without the need forlarge and/or expensive cooling systems. In some embodiments of thesystems disclosed herein, amplifiers controlled by a power managementsystem 1040_1 can be configured to turn on/off the amplifier based onthe presence/absence of the signal to be amplified as well as adjust thegate bias voltage based on the monitored drain current can functionwithout any cooling systems, such as for example, electrical orelectro-mechanical cooling systems.

FIG. 15 illustrates an example of currents required to charge storagecapacitors for amplifiers utilizing drain switching. As opposed to drainswitching, another advantage of synchronizing the turning on/off thebias voltage to the gate terminal with the turning on/off the inputsignal is an increase in power efficiency. As discussed above, a storagecapacitor 1238 may be provided near the drain terminal of the amplifier1228 in various implementations. Depending on the pulse width and dutycycle requirements, the storage capacitor 1238 can have a largecapacitance value (e.g., between 700 F and 2000 F). If the drain currentis turned on/off synchronously with the input signal, a large amount ofenergy is required to charge the storage capacitor 1238.

FIG. 16 illustrates an example of currents required to charge storagecapacitors for amplifiers utilizing gate switching. In contrast, thecapacitors near the gate terminal have lower capacitance values and theenergy required to charge those capacitors can be between 10-20 timeslower than the energy required to charge the storage capacitor 1238.Accordingly turning on/off the gate bias voltage (referred to herein asgate switching) instead of modulating the drain current/voltage(referred to herein as drain switching) can advantageously increasepower efficiency of the amplifier.

FIG. 17 illustrates a flow chart of exemplary operations for currentsensing performed by the power management system 1040_1. The drainand/or gate current from the amplifier can be monitored as shown inblock 1704. As discussed above, the drain and/or gate current can bemonitored using the sensing system 1121. The drain and/or gate currentcan be sensed continuously or intermittently (e.g., periodically). Asdiscussed above, the sensed current can be sampled and averaged toobtain a measurement of the current. The current can be correlated to atemperature as discussed above. In various implementations, a range forthe drain and/or gate current defined by an upper current thresholdvalue and a lower current threshold value can be provided for variousgate bias voltages. For a given gate bias voltage, the power efficiencyof the amplifier is optimized if the drain and/or gate current is withinthe provided current range. Accordingly, if the measured current isdifferent from a threshold value (upper current threshold or lowercurrent threshold) as shown in block 1706, then the gate bias voltagecan be changed as shown in block 1708. The power management system1040_1 can change the gate bias voltage when the incoming signal isturned off or in-between pulses of the incoming signal. Otherwise, theoperation can continue as shown in block 1710.

FIG. 18 illustrates an exemplary process for monitoring and tuning anamplifier. A reset command can be received to commence an initializationoperation 1800. The digital-to-analog converter can be initialized 1802.The initialization can include setting the voltage range of the DAC toappropriate output values for an amplifier being controlled, such as+/−5V.

Once the DAC voltage is set, an idle state 1804 can be entered. The idlestate can be maintained until a tune command is received. A tune commandcan invoke a DAC prepare state 1806, where the voltage can be set to aspecified level, such as −5V. A sensor calibration state 1808 can thenbe entered. In one embodiment, the sensor can be calibrated for a zeroamp voltage offset. The offset can be subtracted from incoming samplesat the analog-to-digital converter interface that can receive a currentsense signal from a current sensor, such as one that may be part ofsensing system 1121. If the offset is less than a threshold, an errorstate 1812 can be entered. Otherwise, a tune state 1810 can be entered.In this state, a new bias voltage (Vg) can be applied as an offset todirect the current sense signal to the desired value. If the DAC ismaxed out, the error state 1812 can be entered. Otherwise, a completionstate 1814 can be entered to determine whether processing should returnto state 1806 to try to obtain an improved current sense signal.

The operations of FIG. 18 may be substituted with other approaches toestablish an optimal current range. For example, the current range canbe experimentally tested ahead of time and manually programmed or hardcoded into the system. The system can also use machine learning orartificial intelligence techniques to find the optimal current. In otherembodiments, signals are fed back into the tuning algorithm instead ofjust the current. Other signals include the RF output signal 420. Acoupler can be used to determine the RF output level. For example, abias voltage may be applied, a test RF signal is sent, which is readthrough the coupler into the RF signal generator 1050 [in FIG. 11]. Thisprocedure is repeated until an optimal saturated RF power output valueis obtained. Different optimization criteria are available, such asoptimize for power out, such as to achieve 3 dB into power amplifiersaturation. Another possible criterion can be to optimize for linearity,such that the RF power is in the linear range. In one embodiment, apre-programmed voltage bias can be used and then voltage adjustments,e.g., 1, 5, or 10 mV, above and below the pre-programmed voltage can beused until the optimal voltage is achieved.

The RF output power can be tracked by the coupler and this informationis relayed to the power management system 1040_1. As the RF power outfor a given bias voltage or current for a given bias voltage starts todrop, the power management system 1040_1 recognizes that the amplifieris degrading. The amount of degradation can be mapped to the lifetime ofthe amplifier. Reports on amplifier state can be periodically issued bythe power management system 1040_1.

FIG. 19 illustrates an exemplary embodiment of a display showing thehealth of an amplifier system. The power management system 1040_1 caninclude instructions executed by electronic processing system 811 torender to display device (e.g., a computer/monitor) the state of thevarious amplifiers being controlled by the power management system1040_1. The depicted example display shows the health of a systemcomprising, for instance, 144 amplifiers arranged in twelve columns andtwelve rows. Each amplifier is represented by a circle 1902. A printedcircuit board or power supply board is associated with each column, asrepresented by a square 1904. Indicia can be provided to characterizethe operational state of each element. For example, a down arrow orcolor red may represent a failed state. Side arrows or amber color mayrepresent a state transition. An up arrow or color green may represent ahealthy state. Absent indicia may represent an off state. This canprovide a graphical display useful for maintaining amplifier health in anumber of ways as disclosed herein. For example, as discussed above, thepower management system 1040_1 may enforce a limit on the bias voltage,drain current, duration of time the amplifier is turned on, and thestate of voltages, currents, being within (or beyond) limits, ormalfunctions, can be displayed. It is understood that the particularnumbers of elements of the display can vary with the particulars of agiven amplifier system, such as if there are more or fewer amplifiers,or if they are arranged in a different physical array.

FIG. 20 illustrates an exemplary block diagram depicting a computerarchitecture for providing distributed IP addresses to amplifier modulesin an arrayed system, such as, for example, the system 100 depicted inFIG. 1, the system depicted in FIG. 9 and/or the system depicted in FIG.10. In some embodiments, each amplifier module (e.g., amplifier chain1070_1, amplifier modules 170, modular power amplifier 800) can bemanufactured to be similar to every other amplifier module such thatthey are easily replaceable. Barring differences in components due tomanufacturing/assembly, it may be preferable to not have the amplifiermodules unique in either hardware terms or software terms. However, inmany applications, such as, for example, a phased array system, toperform beam steering, the operating conditions of the variousamplifiers in an amplifier module can be different depending on thephysical position of a particular amplifier module in the array. Forexample, the amount of gain provided by the amplifiers in the leftmostamplifier module in the array can be different from the amount of gainprovided by the amplifiers in LRAMs in the central portions of the arrayand/or the rightmost amplifier module. Accordingly, some disclosedembodiments are configured to allow each amplifier module to determine(or allow a connected computer system to determine) what gain thevarious amplifiers in that amplifier module should provide andaccordingly what bias voltages should be provided.

In other systems, there can be hardware pins that would indicate theposition (e.g., a digital address) of the amplifier module in the arraywhich in turn would determine bias voltages that should be provided tothe various amplifiers in that amplifier based on its position in thearray. For example, each hardware pin would provide a digital address tothe amplifier module so that they can be addressed.

In various embodiments of arrayed systems disclosed herein, theamplifier modules can be arranged in a plurality of rows and columns.The number of rows and columns can vary between 1 and 20 in someimplementations. The number of rows can be different from the number ofcolumns. An example implementation of an arrayed system comprising aplurality of rows and a plurality of columns is shown in FIG. 20. Thearrayed system comprises a signal generator 2040, a central switch 2030,and a plurality of column switches 2010_1 a, 2010_1 b, . . . , 2010_Na,2010_Nb. In the illustrated implementation, each column has two columnswitches that are connected to 6 different amplifier modules. The twoswitches associated with each column are connected to each other. Inother implementations, there can be only 1 switch per column, but ingeneral there can be any number of column switches. The column switchescan be connected to a central switch 2030 which can be in communicationwith the signal generator 2040 (which may be, e.g., RF generator 1050).

In certain embodiments, the column switches and the central switch canbe ethernet switches. Ports of the column switch can be configured as avirtual local area network (VLAN). In various implementations, each portof the column switch can be assigned its own subnet. Any device thatplugs into a port of the column can thus be on its own network and neednot be in communication with their neighbors. A Dynamic HostConfiguration Protocol (DHCP) server within the central switch 2030and/or the signal generator 2040 and/or column switch 2010 can have acomplete listing of the network address for each port. When an amplifiermodule gets plugged in to a port of a column, a message requesting an IPaddress and providing the port's subnet address is sent over thenetwork. The message can be sent by the amplifier module or a networkelement connected to the port which detects the presence of theamplifier module. The signal generator 2040 and/or the central switch2030 and/or column switch 2010 can determine which subnet the requestoriginated from and can assign a unique IP address to that amplifiermodule. This address can be unique to the port of the column switch andnot to the amplifier module. For example, an amplifier module plugged incolumn 1: row 1 can be given the address 10.1.1.254, an amplifier moduleplugged in column 1: row 6 can be given the address 10.1.6.254, anamplifier module plugged in column 2: row 12 can be given the address10.2.12.254, and an amplifier module plugged in column 12: row 12 can begiven the address 10.12.12.254. If the amplifier modules in column 1:row 1 and column 12: row 12 are swapped, then each of those would getnew addresses based on the new ports they are plugged in to. Thus, eachamplifier module can be dynamically addressed based on its locationwithout reconfiguring hardware or software.

In some embodiments, as shown in FIG. 20, a column switch can beconnected to half of the modular power amplifiers in a column of thearray of ports, where the software causes routing assignment of the IPaddress through the column switch. In some embodiments, the software canassign a subnet address to a column switch. The assigning of the IPaddress to the modular power amplifier can accordingly be based on themodular power amplifier specifying the subnet address and the columnposition.

This addressing scheme is easily scalable without requiring any hardwarein the amplifier module harness or any special software to read theaddress during bootup as would be required when hardware pins are usedto address an individual amplifier module. Thus, the disclosedembodiments can simplify the start-up procedures and reduce the amountof time required to start-up and/or replace an amplifier module.

Beyond applications in the RF generation field, the discloseddistributed addressing scheme can be used in a variety of othertechnologies such as in hardware/optical switches, routers, or otherdistributed systems in which there are replacements elements whoseoutput depends on the position in the system. Furthermore, the disclosedembodiments of any of the address as described above can be combinedwith the current/voltage sensing capabilities described with otherembodiments herein.

This way, the present disclosure contemplates combining any of thedisclosed embodiments to provide a system with numerous technicaladvantages over conventional systems.

In the following, further features, characteristics, and exemplarytechnical solutions of the present disclosure will be described in termsof items that may be optionally claimed in any combination:

Item 1: A system comprising a modular power amplifier comprising a poweramplifier subsystem comprising a first 90 degree hybrid block configuredto receive an RF signal and output a split RF signal with componentshaving a 90 degree phase shift; a second 90 degree hybrid blockconfigured to receive and combine the split RF signal by removing the 90degree phase shift; and a high-power amplifier configured to amplify atleast one of the components of the split RF signal; a power distributionmodule configured to regulate an amount of power input to the high-poweramplifier; and a power sequencer configured to control the timing ofpower delivery by the power distribution module.

Item 2: The system of any one of the preceding items, the first 90degree hybrid block further comprising a resistor configured todissipate at least a portion of RF power going through the first 90degree hybrid block when the RF power is above a threshold.

Item 3: The system of any one of the preceding items, comprising aplurality of power amplifier subsystems, each of the power amplifiersubsystems including the first hybrid block and the second hybrid block,where at least one of the plurality of the power amplifier subsystemsreplaces a high-power amplifier in another of the plurality of poweramplifier subsystems to form a scaled power amplifier assembly.

Item 4: The system of any one of the preceding items, wherein theplurality of power amplifier subsystems includes at least four poweramplifier subsystems to form the scaled power amplifier assembly.

Item 5: The system of any one of the preceding items, furthercomprising: a power divider coupled to a plurality of the modular poweramplifiers arranged in parallel and configured to receive and amplifyrespective RF signals from the power divider; and a high-power combinerassembly coupled to the plurality of the modular power amplifiers andconfigured to combine respective RF output signals from the plurality ofthe modular power amplifiers.

Item 6: The system of any one of the preceding items, further comprisingwaveform generation circuitry comprising: a field-programmable gatearray and a digital-to-analog converter, together configured to receivedigital commands and a clock synchronization signal and to output the RFsignal to the power amplifier subsystem; and a phase lock loop circuitconfigured to provide clocking to the power amplifier synchronized withthe clock synchronization signal.

Item 7: The system of any one of the preceding items, wherein thedigital-to-analog converter is configured to output an intermediatefrequency of the RF signal, and the system further comprising: a mixersubsystem configured to upconvert the RF signal from the intermediatefrequency to a final frequency going into the power amplifier subsystem.

Item 8: The system of any one of the preceding items, further comprisingwaveform generation circuitry comprising: a direct digital synthesizerchip configured to receive digital commands and a clock synchronizationsignal and to output the RF signal to the power amplifier subsystem; anda phase lock loop circuit configured to provide clocking to the poweramplifier synchronized with the clock synchronization signal.

Item 9: A system comprising: a power amplifier subsystem comprising: asplitter configured to split an RF signal into a first RF component anda second RF component; a first high-power amplifier configured toamplify and output the first RF component; and a second high-poweramplifier configured to amplify and output the second RF component; anda differential antenna having a first input operatively connected to thefirst high-power amplifier to receive the first RF component and asecond input operatively connected to the second high-power amplifier toreceive the second RF component.

Item 10: The system of any one of the preceding items, wherein thedifferential antenna is a high-impedance low-profile aperture.

Item 11: The system of any one of the preceding items, furthercomprising a connected dipole array or a long-slot array antenna, eitherincluding a plurality of the high-impedance low-profile apertures.

Item 12: A system comprising: a modular power amplifier having two poweramplifier subsystems, each comprising: a first 90 degree hybrid blockconfigured to receive an RF signal and output a split RF signal withcomponents having a 90 degree phase shift; a high-power amplifierconfigured to amplify at least one of the components of the split RFsignal; and a second 90 degree hybrid block configured to receive,combine, and output the split RF signal by removing the 90 degree phaseshift; and a differential antenna configured to receive the output ofthe second 90 degree hybrid blocks of the two power amplifiersubsystems.

Item 13: A three-dimensional power amplifier comprising: a firsthigh-power amplifier configured to receive a first RF signal and outputa first amplified RF signal; and a second high-power amplifierconfigured to receive a second RF signal and output a second amplifiedRF signal, the second high-power amplifier having a differentorientation than the first high-power amplifier, the differentorientations causing a reduction in electromagnetic interference betweenthe first high-power amplifier and the second high-power amplifier.

Item 14: The three-dimensional power amplifier of any one of thepreceding items, wherein the first high-power amplifier and the secondhigh-power amplifier are of generally planar construction and thegenerally planar amplifiers have the different orientations.

Item 15: The three-dimensional power amplifier of any one of thepreceding items, wherein the first high-power amplifier and the secondhigh-power amplifier are constructed on printed circuit boards anddisposed to have the different orientations.

Item 16: The three-dimensional power amplifier of any one of thepreceding items, wherein the different orientations have an angle of 90degrees between them to form a portion of a square distribution ofhigh-power amplifiers.

Item 17: The three-dimensional power amplifier of any one of thepreceding items, wherein the different orientations have an angle of 120degrees between them to form a portion of a hexagonal distribution ofhigh-power amplifiers.

Item 18: The three-dimensional power amplifier of any one of thepreceding items, wherein the different orientations have an angle of 60degrees between them to form a portion of a triangular distribution ofhigh-power amplifiers.

Item 19: The three-dimensional power amplifier of any one of thepreceding items, further comprising a third high-power amplifier havingan orientation substantially perpendicular to the first high-poweramplifier and a fourth high-power amplifier having an orientationsubstantially perpendicular to the second high-power amplifier .

Item 20: The three-dimensional power amplifier of any one of thepreceding items, further comprising a cooling component located betweenthe first high-power amplifier and the second high-power amplifier.

Item 21: The three-dimensional power amplifier of any one of thepreceding items, further comprising electromagnetic shielding adjacentthe first high-power amplifier or the second high-power amplifier.

Item 22: The three-dimensional power amplifier of any one of thepreceding items, wherein the first high-power amplifier and the secondhigh-power amplifier are configured to receive the first RF signal andthe second RF signal, both signals having a wavelength, and the firsthigh-power amplifier and the second high-power amplifier are separatedby at least approximately half of the wavelength.

Item 23: A system comprising: an RF generator configured to generate RFsignals having a wavelength; a plurality of amplifiers configured toreceive and amplify the RF signals from the RF generator and that areseparated from each other by a separation distance in a range betweenapproximately 0.3 times the wavelength and approximately 0.7 times thewavelength; and a power management system configured to control one ormore of the plurality of amplifiers based on information received thatis associated with the RF signals.

Item 24: The system as in any one of the preceding items, wherein theseparation between the plurality of amplifiers is at least approximately0.7 times the wavelength.

Item 24: The system as in any one of the preceding items, wherein theseparation between the plurality of amplifiers is at least approximately0.3 times the wavelength or at least approximately 0.5 times thewavelength.

Item 25: The system as in any one of the preceding items, wherein thewavelength is within the L-band.

Item 26: The system as in any one of the preceding items, wherein theseparation between the plurality of amplifiers is between approximately3-7 inches.

Item 27: The system as in any one of the preceding items, wherein the RFgenerator is configured to generate a plurality of wavelengths of RFsignals and the separation between the plurality of amplifiers isapproximately the smallest wavelength of the plurality of wavelengths.

Item 28: The system as in any one of the preceding items, wherein thepower management system is configured to automatically determinevoltages and/or currents required to turn-on and/or turn-offcorresponding amplifiers in the plurality of amplifiers.

Item 29: The system as in any one of the preceding items, wherein thepower management system is configured to perform the automaticdetermination prior to the RF generator generating the RF signals.

Item 30: The system as in any one of the preceding items, wherein thepower management system is configured to access computer memory toobtain historical data stored from prior operations of the system,wherein the automatic determination is based at least partially on thehistorical data.

Item 31: The system as in any one of the preceding items, wherein thepower management system is further configured to: detect whether the RFsignal to be amplified is turned on or off; and generate a gate voltageor a gate current sufficient to turn on an amplifier responsive todetecting that the RF signal is turned on and turn off the amplifierresponsive to detecting that the RF signal is turned off.

Item 32: The system as in any one of the preceding items, wherein thepower management system is configured to generate the gate voltage orgate current at a rate between 10 MHz and 100 MHz.

Item 33: The system as in any one of the preceding items, wherein thepower management system is configured to generate the gate voltage orgate current at a rate between 1 kHz and 500 MHz.

Item 34: The system as in any one of the preceding items, wherein thepower management system is further configured to: receive a trigger fromthe RF generator that the RF signal will be turned on; and initiate apower sequencing process comprising obtaining, from a computer memory,voltages and/or currents for biasing the amplifier prior to arrival ofthe RF signal.

Item 35: The system as in any one of the preceding items, wherein thesystem does not include a cooling system.

Item 36: The system as in any one of the preceding items, the pluralityof amplifiers comprising: a first high-power amplifier configured toreceive a first RF signal and output a first amplified RF signal; and asecond high-power amplifier configured to receive a second RF signal andoutput a second amplified RF signal, the second high-power amplifierhaving a different orientation than the first high-power amplifier, thedifferent orientations causing a reduction in electromagneticinterference between the first high-power amplifier and the secondhigh-power amplifier.

Item 37: The system as in any one of the preceding items, wherein thefirst high-power amplifier and the second high-power amplifier are ofgenerally planar construction and the generally planar amplifiers havethe different orientations.

Item 38: The system as in any one of the preceding items, wherein thefirst high-power amplifier and the second high-power amplifier areconstructed on printed circuit boards and disposed to have the differentorientations.

Item 39: The system as in any one of the preceding items, wherein thedifferent orientations have an angle of 90 degrees between them to forma portion of a square distribution of high-power amplifiers.

Item 40: The system as in any one of the preceding items, wherein thedifferent orientations have an angle of 120 degrees between them to forma portion of a hexagonal distribution of high-power amplifiers.

Item 41: The system as in any one of the preceding items, wherein thedifferent orientations have an angle of 60 degrees between them to forma portion of a triangular distribution of high-power amplifiers.

Item 42: The system as in any one of the preceding items, furthercomprising a third high-power amplifier having an orientationsubstantially perpendicular to the first high-power amplifier and afourth high-power amplifier having an orientation substantiallyperpendicular to the second high-power amplifier.

Item 43: The system as in any one of the preceding items, furthercomprising a cooling component located between the first high-poweramplifier and the second high-power amplifier.

Item 44: The system as in any one of the preceding items, furthercomprising electromagnetic shielding adjacent the first high-poweramplifier or the second high-power amplifier.

Item 45: The system as in any one of the preceding items, furthercomprising a non-transitory, machine-readable medium storinginstructions which, when executed by at least one programmableprocessor, cause operations comprising: transmitting, from an amplifierof the plurality of amplifiers, a request for an IP address;transmitting, from the amplifier, a subnet address of the amplifierbased on a port that the amplifier is connected to; and assigning, by anaddress server, an IP address to the amplifier based on the subnetaddress of the amplifier.

Item 46: A system comprising: an RF generator configured to generate RFsignals having a wavelength; a plurality of amplifiers configured toreceive and amplify the RF signals from the RF generator and that areseparated from each other by at least approximately half of thewavelength; a sensor configured to detect at least one sensedcharacteristic associated with at least one amplifier of the pluralityof amplifiers; and a power management system configured to control oneor more of the plurality of amplifiers based on the sensedcharacteristic.

Item 47: The system as in any one of the preceding items, wherein theseparation between the plurality of amplifiers is at least approximately0.7 times the wavelength.

Item 48: The system as in any one of the preceding items, wherein theseparation between the plurality of amplifiers is at least approximately0.3 times the wavelength.

Item 49: The system as in any one of the preceding items, wherein thewavelength is within the L-band.

Item 50: The system as in any one of the preceding items, wherein theseparation between the plurality of amplifiers is approximately 5inches.

Item 51: The system as in any one of the preceding items, wherein the RFgenerator is configured to generate a plurality of wavelengths of RFsignals and the separation between the plurality of amplifiers isapproximately the smallest wavelength of the plurality of wavelengths.

Item 52: The system as in any one of the preceding items, wherein thepower management system is configured to automatically determinevoltages and/or currents required to turn-on and/or turn-offcorresponding amplifiers in the plurality of amplifiers.

Item 53: The system as in any one of the preceding items, wherein thepower management system is configured to perform the automaticdetermination prior to the RF generator generating the RF signals.

Item 54: The system as in any one of the preceding items, wherein thepower management system is configured to access computer memory toobtain historical data stored from prior operations of the system,wherein the automatic determination is based at least partially on thehistorical data.

Item 55: The system as in any one of the preceding items, wherein thepower management system is further configured to modify a bias voltageor a bias current of one or more of the plurality of amplifiers.

Item 56: The system as in any one of the preceding items, the pluralityof amplifiers comprising: a first high-power amplifier configured toreceive a first RF signal and output a first amplified RF signal; and asecond high-power amplifier configured to receive a second RF signal andoutput a second amplified RF signal, the second high-power amplifierhaving a different orientation than the first high-power amplifier, thedifferent orientations causing a reduction in electromagneticinterference between the first high-power amplifier and the secondhigh-power amplifier.

Item 57: The system as in any one of the preceding items, wherein thefirst high-power amplifier and the second high-power amplifier are ofgenerally planar construction and the generally planar amplifiers havethe different orientations.

Item 58: The system as in any one of the preceding items, wherein thefirst high-power amplifier and the second high-power amplifier areconstructed on printed circuit boards and disposed to have the differentorientations.

Item 59: The system as in any one of the preceding items, wherein thedifferent orientations have an angle of 90 degrees between them to forma portion of a square distribution of high-power amplifiers.

Item 60: The system as in any one of the preceding items, wherein thedifferent orientations have an angle of 120 degrees between them to forma portion of a hexagonal distribution of high-power amplifiers.

Item 61: The system as in any one of the preceding items, wherein thedifferent orientations have an angle of 60 degrees between them to forma portion of a triangular distribution of high-power amplifiers.

Item 62: The system as in any one of the preceding items, furthercomprising a third high-power amplifier having an orientationsubstantially perpendicular to the first high-power amplifier and afourth high-power amplifier having an orientation substantiallyperpendicular to the second high-power amplifier.

Item 63: The system as in any one of the preceding items, furthercomprising a cooling component located between the first high-poweramplifier and the second high-power amplifier.

Item 64: The system as in any one of the preceding items, furthercomprising electromagnetic shielding adjacent the first high-poweramplifier or the second high-power amplifier.

Item 65: The system as in any one of the preceding items, wherein thesensor is a current sensor.

Item 66: The system as in any one of the preceding items, wherein thecurrent sensor is a drain current sensor that monitors a drain currentof one or more of the plurality of amplifiers.

Item 67: The system as in any one of the preceding items, wherein thecurrent sensor is a gate current sensor that monitors a gate current ofone or more of the plurality of amplifiers.

Item 68: The system as in any one of the preceding items, wherein thesystem is configured to: compare a sensed current value obtained fromthe drain current sensor to a threshold value; and identify an amplifiererror state of one or more of the plurality of amplifiers.

Item 69: The system as in any one of the preceding items, wherein thesystem is further configured to: determine an amount by which a voltageor a current provided to one or more of the plurality of amplifiersshould be offset based on the amplifier error state; and apply theoffset to one or more of the plurality of amplifiers.

Item 70: The system as in any one of the preceding items, wherein thepower management system is further configured to modify a drain voltageor a drain current at a drain terminal of one or more of the pluralityof amplifiers.

Item 71: The system as in any one of the preceding items, wherein thepower management system is further configured to turn off one or more ofthe plurality of amplifiers responsive to the sensed characteristicbeing above a limit.

Item 72: The system as in any one of the preceding items, wherein thesensed characteristic is a temperature.

Item 73: The system as in any one of the preceding items, wherein thesensor is a current sensor and the power management system is furtherconfigured to determine a temperature based on a drain current of one ormore of the plurality of amplifiers as detected with the current sensor.

Item 74: The system as in any one of the preceding items, wherein thepower management system is further configured to adjust a bias voltageor a bias current based on the detected drain current to improve anoperational characteristic of one or more of the plurality ofamplifiers.

Item 75: The system as in any one of the preceding items, wherein thesensor is a temperature sensor configured to sense an ambienttemperature in the vicinity of one or more of the plurality ofamplifiers.

Item 76: The system as in any one of the preceding items, wherein thepower management system is further configured to: determine, at leastintermittently, the temperature of one or more of the plurality ofamplifiers; and adjust a bias voltage or a bias current of one or moreof the plurality of amplifiers based on the determined temperature toimprove an operational characteristic of one or more of the plurality ofamplifiers.

Item 77: The system as in any one of the preceding items, wherein thesensor is a current sensor and the power management system is furtherconfigured to determine a temperature based on a gate current of one ormore of the plurality of amplifiers as detected with the current sensor.

Item 78: The system as in any one of the preceding items, wherein thepower management system is further configured to adjust a bias voltageor a bias current based on the detected gate current to improve anoperational characteristic of one or more of the plurality ofamplifiers.

Item 79: The system as in any one of the preceding items, wherein thepower management system is further configured to: turn on or off one ormore of the plurality of amplifiers based on a presence or absence ofthe RF signals to be amplified; and adjust a bias voltage or currentbased on a drain current as sensed with the sensor.

Item 80: The system as in any one of the preceding items, wherein thepower management system is further configured to perform operationscomprising: monitoring a drain and/or gate current with the sensor;determining that the drain current and/or gate current is outside acurrent range that is based on a gate voltage of one or more of theplurality of amplifiers; determining a gate voltage that causes thedrain and/or gate current to be within the current range; and providingthe gate voltage to one or more of the plurality of amplifiers toimprove the operation of one or more of the plurality of amplifiers.

Item 81: The system as in any one of the preceding items, furthercomprising: a display device; at least one programmable processor; and anon-transitory machine-readable medium storing instructions which, whenexecuted by the at least one programmable processor, cause the at leastone programmable processor to perform operations comprising: determiningoperational states of the plurality of amplifiers based at least on theat least one sensed characteristic; and displaying, at the displaydevice, indicia characterizing the operational states of the pluralityof amplifiers.

Item 82: The system as in any one of the preceding items, furthercomprising a non-transitory, machine-readable medium storinginstructions which, when executed by at least one programmableprocessor, cause operations comprising: transmitting, from an amplifierof the plurality of amplifiers, a request for an IP address;transmitting, from the amplifier, a subnet address of the amplifierbased on a port that the amplifier is connected to; and assigning, by anaddress server, an IP address to the amplifier based on the subnetaddress of the amplifier.

Item 83: A computer program product comprising a non-transitory,machine-readable medium storing instructions which, when executed by atleast one programmable processor, cause operations comprising:transmitting, from a modular component, a request for an IP address;transmitting, from the modular component, a subnet address of themodular component based on a port that the modular component isconnected to; and assigning, by an address server, an IP address to themodular component based on the subnet address of the modular component.

Item 84: The computer program product as in any one of the precedingitems, wherein the modular component is a modular power amplifierconfigured to amplify an RF signal.

Item 85: The computer program product as in any one of the precedingitems, the operations further comprising providing a bias voltage to themodular power amplifier based on the IP address.

Item 86: The computer program product as in any one of the precedingitems, wherein the address server is a Radio Frequency System-on-Chip(RFSoC).

Item 87: The computer program product as in any one of the precedingitems, wherein the assigning of the IP address is based on a row and acolumn of the port in an array of ports configured to connect to modularpower amplifiers.

Item 88: The computer program product as in any one of the precedingitems, wherein the IP address is assigned further based on a columnswitch that a modular power amplifier is connected to and based on acolumn position of the modular power amplifier as connected to thecolumn switch, wherein the column switch connects a plurality of modularpower amplifiers connected to the array of ports.

Item 89: The computer program product as in any one of the precedingitems, wherein the column switch is connected to all modular poweramplifiers in a column of the array of ports, the operations furthercomprising routing assignment of the IP address through the columnswitch.

Item 90: The computer program product as in any one of the precedingitems, wherein the column switch is connected to half of the modularpower amplifiers in a column of the array of ports, the operationsfurther comprising routing assignment of the IP address through thecolumn switch.

Item 91: The computer program product as in any one of the precedingitems, the operations further comprising assigning, to the columnswitch, the subnet address, and wherein the assigning of the IP addressto the modular power amplifier is based on the modular power amplifierspecifying the subnet address and the column position.

Item 92: The computer program product as in any one of the precedingitems, the operations further comprising raising and/or lowering thegate voltage of the modular power amplifier to synchronize gating themodular power amplifier with an incoming RF signal.

Item 93: The computer program product as in any one of the precedingitems, the operations further comprising measuring a characteristic ofthe modular power amplifier and adjusting a gate bias voltage of themodular power amplifier.

Item 94: The computer program product as in any one of the precedingitems, wherein the characteristic is a temperature of the modular poweramplifier, and the operations further comprising adjusting the gate biasvoltage to maintain the temperature to be approximately a thresholdtemperature.

Item 95: The computer program product as in any one of the precedingitems, wherein the characteristic is a linearity measure of the modularpower amplifier, and the operations further comprising adjusting thegate bias voltage to maintain the linearity measure to be approximatelya predetermined linearity measure.

One or more aspects or features of the subject matter described hereincan be realized in digital electronic circuitry, integrated circuitry,specially designed application specific integrated circuits (ASICs),field programmable gate arrays (FPGAs) computer hardware, firmware,software, and/or combinations thereof. These various aspects or featurescan include implementation in one or more computer programs that areexecutable and/or interpretable on a programmable system including atleast one programmable processor, which can be special or generalpurpose, coupled to receive data and instructions from, and to transmitdata and instructions to, a storage system, at least one input device,and at least one output device. The programmable system or computingsystem may include clients and servers. A client and server aregenerally remote from each other and typically interact through acommunication network. The relationship of client and server arises byvirtue of computer programs running on the respective computers andhaving a client-server relationship to each other.

These computer programs, which can also be referred to programs,software, software applications, applications, components, or code,include machine instructions for a programmable processor, and can beimplemented in a high-level procedural language, an object-orientedprogramming language, a functional programming language, a logicalprogramming language, and/or in assembly/machine language. As usedherein, the term “machine-readable medium” (or “computer readablemedium”) refers to any computer program product, apparatus and/ordevice, such as for example magnetic discs, optical disks, memory, andProgrammable Logic Devices (PLDs), used to provide machine instructionsand/or data to a programmable processor, including a machine-readablemedium that receives machine instructions as a machine-readable signal.The term “machine-readable signal” (or “computer readable signal”)refers to any signal used to provide machine instructions and/or data toa programmable processor. The machine-readable medium can store suchmachine instructions non-transitorily, such as for example as would anon-transient solid-state memory or a magnetic hard drive or anyequivalent storage medium. The machine-readable medium can alternativelyor additionally store such machine instructions in a transient manner,such as for example as would a processor cache or other random accessmemory associated with one or more physical processor cores.

To provide for interaction with a user, one or more aspects or featuresof the subject matter described herein can be implemented on a computerhaving a display device, such as for example a cathode ray tube (CRT) ora liquid crystal display (LCD) or a light emitting diode (LED) monitorfor displaying information to the user and a keyboard and a pointingdevice, such as for example a mouse or a trackball, by which the usermay provide input to the computer. Other kinds of devices can be used toprovide for interaction with a user as well. For example, feedbackprovided to the user can be any form of sensory feedback, such as forexample visual feedback, auditory feedback, or tactile feedback; andinput from the user may be received in any form, including, but notlimited to, acoustic, speech, or tactile input. Other possible inputdevices include, but are not limited to, touch screens or othertouch-sensitive devices such as single or multi-point resistive orcapacitive trackpads, voice recognition hardware and software, opticalscanners, optical pointers, digital image capture devices and associatedinterpretation software, and the like.

In the descriptions above and in the claims, phrases such as “at leastone of” or “one or more of” may occur followed by a conjunctive list ofelements or features. The term “and/or” may also occur in a list of twoor more elements or features. Unless otherwise implicitly or explicitlycontradicted by the context in which it used, such a phrase is intendedto mean any of the listed elements or features individually or any ofthe recited elements or features in combination with any of the otherrecited elements or features. For example, the phrases “at least one ofA and B;” “one or more of A and B;” and “A and/or B” are each intendedto mean “A alone, B alone, or A and B together.” A similarinterpretation is also intended for lists including three or more items.For example, the phrases “at least one of A, B, and C;” “one or more ofA, B, and C;” and “A, B, and/or C” are each intended to mean “A alone, Balone, C alone, A and B together, A and C together, B and C together, orA and B and C together.” Use of the term “based on,” above and in theclaims is intended to mean, “based at least in part on,” such that anunrecited feature or element is also permissible.

The subject matter described herein can be embodied in systems,apparatus, methods, computer programs and/or articles depending on thedesired configuration. Any methods or the logic flows depicted in theaccompanying figures and/or described herein do not necessarily requirethe particular order shown, or sequential order, to achieve desirableresults. The implementations set forth in the foregoing description donot represent all implementations consistent with the subject matterdescribed herein. Instead, they are merely some examples consistent withaspects related to the described subject matter. Although a fewvariations have been described in detail above, other modifications oradditions are possible. In particular, further features and/orvariations can be provided in addition to those set forth herein. Theimplementations described above can be directed to various combinationsand subcombinations of the disclosed features and/or combinations andsubcombinations of further features noted above. Furthermore, abovedescribed advantages are not intended to limit the application of anyissued claims to processes and structures accomplishing any or all ofthe advantages.

Additionally, section headings shall not limit or characterize theinvention(s) set out in any claims that may issue from this disclosure.Further, the description of a technology in the “Background” is not tobe construed as an admission that technology is prior art to anyinvention(s) in this disclosure. Neither is the “Summary” to beconsidered as a characterization of the invention(s) set forth in issuedclaims. Furthermore, any reference to this disclosure in general or useof the word “invention” in the singular is not intended to imply anylimitation on the scope of the claims set forth below. Multipleinventions may be set forth according to the limitations of the multipleclaims issuing from this disclosure, and such claims accordingly definethe invention(s), and their equivalents, that are protected thereby.

1. A system comprising: an RF generator configured to generate RFsignals having a wavelength; a plurality of amplifiers configured toreceive and amplify the RF signals from the RF generator and that areseparated from each other by a separation distance in a range betweenabout 0.2 times the wavelength and about 10.0 times the wavelength; anda power management system configured to control one or more of theplurality of amplifiers based on information received that is associatedwith the RF signals. 2-6. (canceled)
 7. The system of claim 1, whereinthe power management system is configured to automatically determinevoltages and/or currents required to turn-on and/or turn-offcorresponding amplifiers in the plurality of amplifiers.
 8. The systemof claim 7, wherein the power management system is configured to performthe automatic determination prior to the RF generator generating the RFsignals.
 9. The system of claim 7, wherein the power management systemis configured to access computer memory to obtain historical data storedfrom prior operations of the system, wherein the automatic determinationis based at least partially on the historical data.
 10. The system ofclaim 1, wherein the power management system is further configured to:detect whether the RF signal to be amplified is turned on or off; andgenerate a gate voltage or a gate current sufficient to turn on anamplifier responsive to detecting that the RF signal is turned on andturn off the amplifier responsive to detecting that the RF signal isturned off.
 11. (canceled)
 12. (canceled)
 13. The system of claim 1,wherein the power management system is further configured to: receive atrigger from the RF generator that the RF signal will be turned on; andinitiate a power sequencing process comprising obtaining, from acomputer memory, voltages and/or currents for biasing the amplifierprior to arrival of the RF signal.
 14. The system of claim 1, whereinthe system does not include a cooling system.
 15. The system of claim 1,the plurality of amplifiers comprising: a first high-power amplifierconfigured to receive a first RF signal and output a first amplified RFsignal; and a second high-power amplifier configured to receive a secondRF signal and output a second amplified RF signal, the second high-poweramplifier having a different orientation than the first high-poweramplifier, the different orientations causing a reduction inelectromagnetic interference between the first high-power amplifier andthe second high-power amplifier.
 16. The system of claim 15, wherein thefirst high-power amplifier and the second high-power amplifier are ofgenerally planar construction and the generally planar amplifiers havethe different orientations. 17-24. (canceled)
 25. A system comprising:an RF generator configured to generate RF signals having a wavelength; aplurality of amplifiers configured to receive and amplify the RF signalsfrom the RF generator and that are separated from each other by aseparation distance approximately 0.2-10.0 times the wavelength; asensor configured to detect at least one sensed characteristicassociated with at least one amplifier of the plurality of amplifiers;and a power management system configured to control one or more of theplurality of amplifiers based on the sensed characteristic. 26-33.(canceled)
 34. The system of claim 25, wherein the power managementsystem is further configured to modify a bias voltage or a bias currentof one or more of the plurality of amplifiers.
 35. The system of claim25, the plurality of amplifiers comprising: a first high-power amplifierconfigured to receive a first RF signal and output a first amplified RFsignal; and a second high-power amplifier configured to receive a secondRF signal and output a second amplified RF signal, the second high-poweramplifier having a different orientation than the first high-poweramplifier, the different orientations causing a reduction inelectromagnetic interference between the first high-power amplifier andthe second high-power amplifier. 36-43. (canceled)
 44. The system ofclaim 25, wherein the sensor is a current sensor.
 45. The system ofclaim 44, wherein the current sensor is a drain current sensor thatmonitors a drain current of one or more of the plurality of amplifiers.46. (canceled)
 47. The system of claim 45, wherein the system isconfigured to: compare a sensed current value obtained from the draincurrent sensor to a threshold value; and identify a deviation from adesired amplifier state of one or more of the plurality of amplifiers.48. The system of claim 47, wherein the system is further configured to:determine an amount by which a voltage or a current provided to one ormore of the plurality of amplifiers should be offset based on thedeviation of the amplifier state; and apply the offset to one or more ofthe plurality of amplifiers.
 49. (canceled)
 50. (canceled)
 51. Thesystem of claim 25, wherein the sensed characteristic is a temperature.52. The system of claim 51, wherein the sensor is a current sensor andthe power management system is further configured to determine atemperature based on a drain current of one or more of the plurality ofamplifiers as detected with the current sensor.
 53. The system of claim51, wherein the power management system is further configured to adjusta bias voltage or a bias current based on the detected drain current toimprove an operational characteristic of one or more of the plurality ofamplifiers.
 54. (canceled)
 55. The system of claim 51, wherein the powermanagement system is further configured to: determine, at leastintermittently, the temperature of one or more of the plurality ofamplifiers; and adjust a bias voltage or a bias current of one or moreof the plurality of amplifiers based on the determined temperature toimprove an operational characteristic of one or more of the plurality ofamplifiers. 56-60. (canceled)
 61. The system of claim 25, furthercomprising a non-transitory, machine-readable medium storinginstructions which, when executed by at least one programmableprocessor, cause operations comprising: in response to detectingpresence of an amplifier: transmitting, a request for an IP address;transmitting, a subnet address of a port connected to the amplifier; andassigning, by an address server, an IP address to the amplifier based onthe subnet address of the amplifier. 62-74. (canceled)